Volume 9 Number 2        July 1993


CYANONEWS - a newsletter intended to provide cyanobacteriologists with a

     forum for rapid informal communication, unavailable through journals.

     Everything you read in this newsletter is contributed by readers like

     yourself. Published occasionally, about three times per year.

SUBSCRIPTIONS - $10 or equivalent/year for a hard copy. Free by E-Mail. 

CONTRIBUTIONS - Expected every couple of years: a new result, an upcoming

     meeting or a summary of a past meeting, a post-doctoral opening, a new

     publication, a request for strains, a change of life... something. See

     last page for addresses you can send news to.


     name is capitalized in the news item. Addresses are given at the end of

     the issue. Also, a Directory of Cyanobacteriologists is distributed every

     two years. 


COPYRIGHT - This newsletter is not copyrighted and no rights are reserved.

     You are encouraged to reproduce or to transmit any part of this

     publication by whatever means at your disposal, no permission required.




  * Meetings

  * Announcements

  * Positions available 


    * Shanghao Li


  * Fremyella,Nostoc plasmids share common features

  * Dune cyanobacteria described, available

  * Spirulina grown on citrus industry effluent

  * Unique rubisco activase in heterocystous cyanos

  * Red cyanobacteria infest coral reefs

  * Genes encoding eukaryotic-type RNA-binding proteins

    found in cyanobacteria

  * Novel method to separate enantiomers: Application to homoanatoxin-a


  * AT-bias and phylogeny of prochlorophytes 


  * 1993 Cyanobacterial Workshop






in Brisbane, will include symposia centered around several themes, some of

which may be: non-symbiotic N2 fixation, microbe-plant genetic interactions,

the role of molecular genetics in microbial ecology, nitrogen fixation in

agricultural production systems, and metabolic pathways associated with

nitrogen fixation.

     Contact: H. Van Bushby, CSIRO Div of Tropical Crops & Pastures,

     306 Carmody Road, Santa Lucia  Qld 4067, Australia. (Fax) 61-7-3713946.

     Or phone P. Dart (61-7-3652867) or Lex Diatloff (61-7-8779311).


Umea, Sweden, will be the site of the EUCHEM-conference on ULTRAFAST

PROCESSES IN CHEMISTRY AND BIOLOGY, 13-16 June, 1994. Amongst the topics to

be addressed are energy transfer and electron transfer in photosynthesis.

     Contact: The Swedish National Committee for Chemistry, Wallingatan 26

     B, S-111 24 Stockholm. (Tel) 46-8-115280, (Fax) 46-8-106678.



10-15 Sep 1994 in Urbino, Italy. In addition to themes common to previous

symposia, e.g., biogenesis, regulation, structure, and function of the

photosynthetic apparatus, metabolism, ecology, and taxonomy, the organizers

have added a new theme: basic and applied biotechnological processes

     Contact: Stefano Ventura, CNR - Centro di Studio dei Microrganismi

     Autotrofi, piazzale delle Cascine 27, I-50144 Firenze Italy.

     (Tel) 39-55-350542, (Fax) 39-55-330431, (E-mail)



CONFERENCE will be held in Harare, Zimbabwe, 12-17 September 1994, focusing

on the agronomic, socio-economic and environmental benefits of biological

nitrogen-fixing systems in Africa.

     Contact: The Secretary, AABNF, Department of Soil Science, University

     of Zimbabwe, Box MP 167, Mount Pleasant, Harare, Zimbabwe.

     (Tel) 263-4-303211 ext 1412. (Fax) 263-4-732828. (Telex) 26580 UNIVZ

     ZW. (Email) (or)


The 8th EUROPEAN BIOENERGETICS CONFERENCE will be held in Valencia, Spain,

12-17 Sep 1994 and will emphasize several topics, including the structure of

energy-transfer proteins, electron-transport systems, light-harvesting

systems, reaction centers, and sodium bioenergetics and salt tolerance. Those

wishing to receive the second announcement should send their complete postal

address, telefax number and areas of interest.

     Contact: Eduardo Rial, EBEC 94, Centro de Investigaciones Biologicas,

     Velazquez 144, 28006 Madrid, Spain. (Fax) 34-1-5627518,

     (Email) ciber12@cc.Csic.Es



tentatively scheduled for August 7-12, 1994. Suggestions regarding the

program (topics, speakers, format, etc.) are welcome. Also, alternative dates

for the meeting will be considered. Send your comments within the next two


     Contact: Marion Thurnauer, Argonne National Laboratory, 9700 S. Cass

     Avenue, Argonne IL 60439 U.S.A. (Tel) 708-252-3545, (Fax) 708-252-9289,

     (E-Mail) or thurnaue@anlchm.bitnet



SOUTH-EAST ASIA AND THE PACIFIC, entitled "Photosynthesis and Productivity

in a Changing Environment", 5-26 Jan 1994 in Bangkok, Thailand. The course

will cover a wide range of topics, including field photosynthesis

measurements, carbon and nitrogen assimilation, algal systems, and biofuels

and energy balance. Applications must arrive by 31st August, 1993 and should

include: (a) a detailed curriculum vitae, (b) a brief description of present

or proposed work and its relevance to the course program, and (c) a letter

of support from an employer or supervisor.

     Contact (applicants from Thailand): Morakot Tanticharoen, School of

         Bioresources and Technology, King Mongkut's Institute of Technology

         Thonburi, Bangmod, Rasburana, Bangkok 10140. (Tel) 66-2-4270039

         ext. 7000, (Fax) 66-2-4279062, 4278077, (Telex) 72383 KMITT TH.

     Contact (applicants from other south-east Asian and Pacific countries:

         David O. Hall, Division of Life Sciences, King's College London,

         University of London, Campden Hill Road, London W8 7AH, UK.

         (Tel) 44-71-3334317, (Fax) 44-71-9377783, (Telex) 8954102 BBSLON G.


JIRI KIVIRANTA has completed and published his Ph.D. dissertation, entitled

Toxins of Cyanobacteria (Blue-Green Algae) -- a Biological and Chemical

Study. One main focus of his work was screening for cyanobacteria toxic to

mosquito larvae. The toxin most effective against mosquitos came from a

hepatotoxic fraction extracted from Microcystis aeruginosa strain 205. It was

analyzed and determined to be [Dha7]microcystin-RR.


     Judy Acreman has sent in a description of the UNIVERSITY OF TORONTO

CULTURE COLLECTION (UTCC), of which she is curator. The UTCC, officially

opened in 1987, makes available cyanobacterial cultures from a collection of

about 250 isolates of freshwater algae and cyanobacteria.  One of the main

goals of the UTCC is to develop a collection of these organisms that is

representative of species native to Canada. Of particular interest are

isolates from areas under environmental stress, for example, acid-stressed

lakes, metal-polluted sites and organically polluted sites.  There are

currently 40 isolates of 24 species of cyanobacteria in the collection, and

more will be added as new isolations proceed. Deposits of research cultures

are welcome, particularly those isolated from locations in Canada. To be

considered for deposit, the cultures should be positively identified at least

to genus and if not axenic, at least have only bacteria present as


     In addition to distributing cultures, the UTCC also offers the following

services: a) custom-isolation of algae and cyanobacteria, b) training in

methods of isolation and culture of these organisms, c) safe-deposit of

cultures on a confidential basis, d) preparation of media.

     To obtain a catalogue of species in culture or for further information


     Judy Acreman, UTCC, Botany Department, University of Toronto, Toronto,

     Ontario, Canada M5S 3B2. (Tel) 416-978-3641, (Fax) 416-978-5878,

     (E-mail) JAcreman@botany.Utoronto.Ca

                             POSITIONS AVAILABLE


CONTACT: Steve Theg, Section of Plant Biology, University of California,

     Davis CA 95616 U.S.A. (Tel) 916-752-0624, (E-mail) SMTheg@UCDavis.Edu

START: After July 1, 1993 

RESEARCH: Study the assembly and function of the three extrinsic subunits of

     the photosynthetic oxygen evolving complex in chloroplasts. The long range

     goals of the project are to identify specific amino acids involved in

     holding the complex together and in imparting its biological activity. 

     The experimental approaches will lean heavily on techniques for random and

     site-directed mutagenesis, in vitro chloroplast protein import, in vitro

     protein reconstitution, and analysis of photosynthetic capacities by

     various biophysical means.

REQUIREMENTS: Ideally, an intimate understanding of photosystem II reactions,

     both theoretical and practical knowledge of molecular biology (cloning,

     sequencing, etc.), experience in biophysical techniques applied to

     chloroplast bioenergetics (i.e., fluorescence, spectroscopy, etc.), and

     familiarity with the field of protein trafficking.  Persons meeting some,

     but not all, of these criteria are still encouraged to apply; clear

     thinking, desire, and solid scientific training will go a long way in

     filling in the gaps.


POSITION: Post-doc

CONTACT: Peter Brzezinski, Department of Biochemistry and Biophysics,

     Chalmers University of Technology, S-412 96 Goteborg, Sweden.

     (Tel) 46-31-7722807, (Fax) 46-31-7722813, 

     (E-mail) Peter@Biofy2.Bcbp.Chalmers.Se

RESEARCH: Use various biophysical and genetic techniques to study bacterial

     and plant photosynthesis. Current work in the project associated with the

     position focuses on reconstitution of PSII in phospholipid vesicles and

     time-resolved measurements of light-induced electrogenic events associated

     with electron and proton transfer. There is great flexibility in the

     design of the project. 

SEND: A brief description of research interests, CV, and the names and

     addresses of at least two references.


POSITION: Post-doc

CONTACT: Terry Bricker, Dept. of Botany, Louisiana State University, Baton

     Rouge LA 70803 U.S.A.

RESEARCH: Molecular biochemistry of photosynthesis. One position involves the

     production and characterization of mutants in the CPa-1 protein of PS II

     [Putnam-Evans & Bricker (92) Biochem 31:11482]. Another involves the study

     of protein-protein interactions in PS II [Frankel & Bricker (92) Biochem


SUPPORT: Initially for 1 year. 

START: Anticipated starting date Sept. 1 1993. 



                         Shanghao Li (1917-1993)

     Shanghao Li passed away suddenly on February 24, 1993 at the Institute of

Hydrobiology of the Chinese Academy of Science in Wuhan. He will be missed

in the scientific communities both in China and abroad as well as by those

of us who knew him directly or indirectly.

     Shanghao Li was born in the Guangzou Province in China. He went to

Zhongshan University to study biology and joined the Institute of

Hydrobiology in the early 1950's. His early research focused on limnology and

the systematics of algae, especially diatoms and green algae. From the mid-

1970's, he studied the physiological ecology of cyanobacteria. He introduced

the method of applying on a grand scale Anabaena as a fertilizer in rice

fields, the success of which was immediately recognized by his colleagues and

by local farmers. The culture collection of algae at the Institute, including

cyanobacteria in his own laboratory, is among the best in Asia. 

     Shanghao Li was the author of numerous research papers and reviews and was

the editor of a number of books. He was often an invited speaker at

international conferences and also hosted many foreign colleagues in China.

He was elected a member of the Chinese Academy of Science in 1980, and in

1981 he was appointed Director of the Institute of Hydrobiology. He served

on several editorial boards of journals and publications (including

CyanoNews) and on organizing committees of conferences.

     To those of us who knew him personally, Professor Li was an outstanding

scientist, a patient teacher, a giving friend, and a man of family. He always

found time for his students, his friends, and his family. We students learned

from his teaching to appreciate the good things in science and to gain

confidence in our research. He was ready to help but seldom mentioned any

unfairness to himself. 

     There were quite a few political movements in China against the educated,

and Professor Li survived each of them, as a cyanobacterium resists adverse

conditions. After 10 years of the Cultural Revolution, he was among the first

to remake contact with the world. He even participated in some political

processes to persuade the government to maintain an open door policy. Many

of his students went abroad to study various aspects of cyanobacteria. While

respecting their opinions, Professor Li always reminded his students that

there were opportunities in China and that China needed well-trained

scientists, not only for its scientific progress but also for its political


     Shanghao Li was also talented in music and Chinese art and literature. He

enjoyed playing piano with his wife and loved walking with his grandson at

sunset along the coast of the beautiful East Lake, where the Institute of

Hydrobiology is located. His life exemplified all that is good in science and

in human beings, an he will be remembered that way.

     Professor Li, we all miss you!

                               -- Jindong Zhao



     MIKE SCHAEFER, recently arrived in his new position in Missouri, reports

a curious finding. He sequenced the origin of replication from pFdAI (a

shuttle vector used in Fremyella) and found it to be very similar to that of

plasmid pDU1, the plasmid from Nostoc PCC 7524 that is the basis for many

shuttle vectors used in Anabaena PCC 7120 and other strains. The similarity

includes an open reading frame of unknown function and regions of dyad

symmetry. Conceivably, the shuttle vectors developed for Anabaena may work

in Fremyella, and Fremyella vectors may work in Anabaenas and Nostocs. Has

anyone ever tried?


     BOB WEBB, another recent arrivee at a new job, this one in Texas, has

isolated some new cyanobacteria from the gypsum dunes at White Sands, New

Mexico. He has two unicellular strains, three filamentous strains, and one

that grows in very short filaments, about four cells within a sheath. The

unicellular strains and two of the filamentous strains grow fairly well on

plates without nitrate. He invites anyone with a possible interest in these

strains to let him know: they are available.


ROGERIO LACAZ-RUIZ has given us a progress report on how he, M.E. Kornfeld,

and M.A. Zanetti in Sao Paulo, Brazil, have used waste water from the citrus

industry to grow Spirulina platensis. The waste water was supplemented with

a wood ash alkaline solution, nitrogen, and phosphorus. They have received

a patent for this growth medium. Spirulina accumulated in this growth medium

at the rate of 0.5 mg/ml during a five day growth period, with little

contamination by green algae. The crude protein content of the biomass was

52% by dry weight. The medium costs US$1.37/liter, 4.2% less than CFTRI, an

alternative synthetic medium.


     BOB TABITA let us know that his laboratory has identified in Anabaena sp.

strain CA three open reading frames downstream from rbcS, encoding the small

subunit of Rubisco. One, labeled rca, encodes Rubisco activase and lies about

2 kb downstream from rbcS. The other two have no recognizable function and

lie between rbcS and rca. Interestingly, rca from Anabaena CA does not show

clear hybridization to DNA from unicellular or nonheterocystous filamentous

cyanobacteria. There is very strong hybridization, however, to DNA from other

strains of Anabaena and Nostoc. The work has recently been published [Plant

Mol Biol 21:753-764].


     Recent times have seen a steady decline in the health of coral reef

ecosystems, and much of this decline may be attributable to coral diseases

associated with cyanobacteria. Two of the most common of the known diseases

affecting coral are black band disease and white band disease. In both cases,

a band of activity sweeps across the coral surface, destroying coral tissue.

Black band consists of a consortium of bacteria, in many ways analogous to

a microbial mat community. The color is due to phycoerythrin from the

dominant species,  Phormidium corallyticum. Much less is known about white

band disease.

     First black, then white... now LAURIE RICHARDSON tells us she has found

a new plague on corals: red band disease. In many ways red band is similar

to black band. The most obvious differences are that the band is brick red

in color and is dominated by a species of the genus Oscillatoria. Unlike

black band, however, red band progresses only in the light and at a much

slower rate of 1 mm per daylight period. It is not clear what controls

movement of the band. In the case of black band, control by light has been

excluded, raising the possibility that chemotaxis is involved. 

     In passing, it should be noted that red band disease has never been

observed outside the Bahamas. Scientists wishing to study the disease must

therefore be willing to spend a significant period in these tropical islands,

a point to consider when choosing an experimental system.


     Those of us who study cyanobacteria often have an interest in eukaryotes

greater than that of your average bacteriologist. This situation arises in

part because at least one ancient member of our chosen class of organisms

snuck into a eukaryote a billion or so years ago, forcing us to comprehend

the behavior of the nucleus in order to appreciate the condition of these

chloroplast descendants. It was ironic, then, to hear two years ago [Kathe

et al (1990) Science 250:1566-1570; Kuhsel et al (1990) Science 250:1570-

1573] that cyanobacteria possess a gene with an intron, that eukaryotic

device previously unknown to bacterial genomes. MARTIN MULLIGAN now comes

with the news that the connection with eukaryotes appears stronger than we

thought. He tells us that heterocyst-forming cyanobacteria have multiple

genes encoding proteins that are similar to the RNP family of eukaryotic RNA-

binding proteins, a family that includes snRNP proteins (responsible for the

excision of introns) and certain regulatory proteins. Previous to this

account, such genes had not been discovered outside of the eukaryotes, unless

one counts chloroplasts as exceptions. 

     Three genes from two strains of cyanobacteria (Anabaena and

Chlorogloeopsis) have been sequenced. All three putative gene products

contain a single RNA Recognition Motif (RRM) that includes the highly

conserved RNP1 and RNP2 regions and all three have a short glycine-rich

carboxy-terminal tail. RNA-binding protein genes are abundant in heterocyst-

forming filamentous cyanobacteria but are not abundant in non-heterocyst-

forming filamentous or unicellular cyanobacteria, raising the possibility

that the cyanobacterial proteins may play a role in gene expression during

heterocyst differentiation.  Although the exact function of the

cyanobacterial gene products is not yet known, their similarity to eukaryotic

proteins suggests that they may play a role in RNA processing - either in

splicing reactions or in processing the 3' end of nascent cyanobacterial

mRNA. The unexpected presence of these genes in cyanobacteria has some

intriguing implications for the evolution of RNA binding proteins and RNA



     Homoanatoxin-a is the neurotoxic compound produced by Oscillatoria

formosa. A new gas chromatographic technique allows the enantiomer-specific

separation of the bicyclic secondary amine, reports OLAV SKULBERG, who

recently developed the procedure in collaboration with John-Erik Haugen and

Michael Oehme (Norwegian Institute for Air Research), Markus Mueller (Swiss

Federal Research Station), and Timothy Gallagher (University of Bristol).

     Separation of cyanophyte neurotoxins into their enantiomers is of

considerable interest. The chemical synthesis of enantiomeric substances

gives a racemate (a precise 1:1 mixture of both enantiomers), while biogenic

formation normally results in a single enantiomer. In many cases, only one

of the enantiomers shows relevant bioactivity. The other is inactive or even

antagonistic. A simple technique to separate enantiomeric neurotoxins


  1. confirmation of the enantiomeric purity of synthetically produced

     neurotoxins that have been separated into single enantiomers by classical

     techniques, such as the formation of diasteriomers.

  2. Identification of the enantiomers formed by cyanophytes, and evaluation

     of the enantiomer-specificity of the biosynthesis.

     Recently, new routine gas chromatographic methods have been developed that

allow the trace level separation of enantiomers on special tailor-made

enantiomeric stationary phases. Such phases consist of a chiral modifier, for

example, a modified cyclodextrin dissolved in a methyl-phenyl-polysiloxane.

This technique permits the separation of the chiral neurotoxin homoanatoxin-a

into its enantiomers.

     Homoanatoxin-a, from extracts of Oscillatoria formosa (NIVA-CYA 92) and

as a synthetic racemic mixture, was transformed into the heptafluorobutyryl

derivative by acylation to obtain a thermally more stable and less polar

compound suitable for gas chromatography. Compounds were detected by negative

ion chemical ionization mass spectrometry (NICI). Mass m/z 315 [M-3HF]- was

used to monitor the compounds in the NICI mode. Figure 1 shows that the

racemic mixture can be completely separated on a glass capillary column as

short as 12 m (0.32 mm i.d.) coated with 20% of a modified beta-cyclodextrin

dissolved in 85% methyl- 15% phenylpolysiloxane. It is evident that the water

extract from the culture of NIVA-CYA 92 contained only one enantiomer. At the

moment, the exact enantiomer conformation of each signal is unknown.

     The method presented has the following advantages:

 *   Complete separation of enantiomers within 15 minutes

 *   Stationary phase is compatible with selective detection using an electron

     capture detector or NICI mass spectrometry

 *   Selectivity and detection limits allow the quantification and enantiomeric

     separation of subpicogram amounts, corresponding to sub-parts per billion

     in water samples

                    [Figure 1 omitted in electronic version]


     In Cyanonews Vol. 8, No. 1, Sean Turner outlined current evidence that no

known prochlorophyte is specifically related to the ancestor of the green

chloroplast and that none of the known prochlorophytes are related to each

other. These conclusions are supported by sequence data from 16S rRNA and

genes encoding RuBp carboxylase, ATP synthase, and DNA-dependent RNA

polymerase [for references see Cyanonews Vol. 8, No. 1, and Origins of

Plastids, R.A. Lewin editor, Chapman & Hall, 1993]. In Cyanonews Vol. 9,

No. 1, Chris Howe questioned these results. His argument was that the high

AT-bias of the chloroplast may artificially group it farther apart from

prochlorophytes with less AT-biased genomes or that unrelated organisms with

convergent %GC content may be grouped together. 

     This criticism ignores two points. The first is that most of the AT-bias

in genes is found in the third position of the codon. The analyses of RNA

polymerase sequence data, for example, did not use the third codon position

for this reason and for the reason that the organisms are too diverged for

this position to contain useful phylogenetic information. The %GC of the

first two codon positions alone of the RNA polymerase fragments of

Prochloron, Prochlorothrix, Prochlorococcus, and maize are quite similar so

that we expect much of the %GC-bias to have been removed. 

     As to the second point: What is the %GC of the genomes of different

prochlorophytes? The work of Herdman suggests that the genome of Prochloron

is 40.5% GC [Arch Microbiol (1981) 129:314-6]. The work of Burger-Wiersma,

et al. suggests that the genome of Prochlorothrix is 53% GC [Int J Systematic

Bacteriol (1989) 39:250-257]. We don't know the %GC of Prochlorococcus. Since

RNA polymerase is a highly expressed protein we would expect its codon usage

and %GC to reflect that of the organism. The %GC based on RNA polymerase

sequences does seem to match that of whole cyanobacterial genomes where each

are known (data not shown). Based on RNA polymerase gene sequences, the %GC

of Prochloron, Prochlorothrix, Prochlorococcus, and maize chloroplast can be

estimated as 42%, 56%, 41-35% (two strains), and 38%, respectively.

Prochlorococcus, in particular, clearly has a high AT-bias -- low %GC. The

third codon position alone is 32% GC and 20% GC, respectively, for two

strains of Prochlorococcus in culture, compared to 27% GC for maize

chloroplast (known to be low %GC) and 79% GC for WH8103, a marine Group A

Synechococcus (known to be high %GC). 

     Despite the apparent high AT-bias of Prochlorococcus, it still groups

closely with marine Group A Synechococcus and shares with them an amino acid

insertion in RNA polymerase found in no other known cyanobacteria. Even with

an AT-bias similar to that of the maize chloroplast, Prochlorococcus does not

group with the green chloroplast lineage. This result suggests that AT-bias

in RNA polymerase gene sequences in general has not been strong enough to

affect the major features of trees derived from those sequences. 

     Although one should always exercise caution in phylogenetic inferences,

sequence data from several molecules providing similar phylogenetic trees

supports the conclusion that the prochlorophytes are a polyphyletic group and

that none of the known prochlorophytes is related to the chloroplast lineage

(though one so related could still be discovered). Chlorophyll b synthesis

thus seems to be an ability either: (1) of ancient origin that has been lost

or has become cryptic in multiple cyanobacterial lineages, (2) that has

migrated by horizontal gene transfer, (3) that has arisen on multiple

occasions by independent mutations, or (4) any combination of the above. 

                               - Brian Palenik


     The 1993 Cyanobacterial Workshop was held May 30 - June 2 at Asilomar

Conference Center, Pacific Grove California. The summaries below represent

only a slice of the hundred or so talks and posters contributed, not to

mention the scientific exchanges that took place against the roar of the

Pacific Ocean. The meeting was organized by Arthur Grossman (Stanford

University) and Mike Schaefer (University of Missouri-Kansas City) who

somehow managed to coordinate matters despite their separation by a couple

of thousand miles. As evidence that the coordination succeeded and was

appreciated by those in attendance, it was decided to model the next meeting

after this last (imitation being the sincerest form of flattery). The next

workshop will be held in 1995, also at Asilomar, organized by Don Bryant

(Pennsylvania State University) and Neil Straus (University of Toronto), who

have no excuses, since they're only about 400 miles apart.


Photosystem I (PS I): Don Bryant (Pennsylvania State University) reported

progress in studying the PS I complex from Synechococcus PCC 7002. In this

cyanobacterium, PS I is comprised of eleven polypeptides namely, PsaA, PsaB,

PsaC, PsaD, PsaE, PsaF, PsaI, PsaJ, PsaK, PsaL and PsaM. The genes encoding

all these polypeptides except PsaI, PsaM and PsaN have been cloned and

characterized. A combination of interposon mutagenesis and overproduction of

some of the above polypeptides in Escherichia coli was used to reveal

information about PS I. PsaD is required for stabilization and correct

orientation of PsaC on the PS I complex, and PsaE polypeptide is required for

cyclic electron transport. Wendy Schluchter (Pennsylvania State University)

told us that PsaK and PsaL mutants grow in DCMU but their growth rates are

slower in low light. PsaL- mutant do not form trimeric PS I complexes.

Furthermore, this mutant exhibits altered state transitions: energy transfer

from the phycobilisome to PS I is impaired. Vim Vermaas (Arizona State

University) reported that a PS I- mutant of Synechocystis PCC 6803 grows at

5 uE/m2תs of light if adapted properly and supplied with sugar. PS II in this

strain shows normal function, and electrons from plastoquinone go to

cytochrome oxidase instead.

Photosystem II (PS II): Himadri Pakrasi (Washington University, St. Louis)

reported complementation of SK18, a mutant of Synechocystis PCC 6803 that

does not have a functional PS II. The open reading frame (ORF) that was

complemented in the mutant shows similarity to a gene from E. coli, prcA,

that encodes a carboxy-terminal processing protease. Interposon mutagenesis

of this ORF in Synechocystis results in a larger D1 protein. Therefore, he

and his colleagues propose that this ORF (designated ctpA) encodes the

carboxy-terminal processing protease for the D1 protein. 

Herbicide resistance: Sergei Shestakov (Moscow State University) reported

complementation of Synechocystis mutants that are resistant to the phenolic

herbicide, dinoseb, and the carotenoid biosynthesis inhibitor, difunone. Gene

inactivation experiments showed that the molecular basis of dinoseb

resistance is associated with the absence of the product of a gene designated

drgA. DrgA does not show homology with any known proteins. It was proposed

that drgA encodes a protein that is involved in the conversion of dinoseb and

metronidazole to highly toxic agents, perhaps through a ferredoxin-dependent

pathway. Difunone resistance results from either a 3 base pair deletion or

a duplication within the dfrA gene. dfrA encodes a product of 74.5 kDa. The

carboxy-terminus shows a helix-turn-helix domain and is homologous to phoR

from B. subtilis, which acts as transcriptional regulator.

Light regulation of psbA gene expression: Susan Golden (Texas A&M University)

gave an update on the differential expression of the psbA gene family in

Synechococcus PCC 7942. Genes psbAII and psbAIII are expressed at very low

levels when cells are grown at low light, but rapidly increase their

expression upon a shift to high light. The levels of psbAI message are high

in low light, but they drop dramatically within a few minutes upon a shift

to high light. After prolonged incubation in high light, the expression of 

the psbAI message increased again to the same levels as is in low light.

After six hours in high light, the total psbA message is four times higher

than before the increase in light intensity. Systematic analysis of the

control regions of psbAII and psbAIII genes showed that three elements are

present upstream of the of each gene: a basal constitutive promoter, a

negative element upstream of the promoter, and a light-responsive element

downstream of the transcription site. The light-responsive elements increase

expression from the native promoter or a heterologous promoter in a position-

and orientation-independent manner indicating enhancer activity. However, the

ability to confer light-responsive expression is orientation-dependent. In

addition, low fluence blue light was shown to elicit the same changes in psbA

expression that are induced by exposure to high light. A pulse of red light

after exposure to blue light significantly attenuates the blue-light-mediated

increase in psbAII and psbAIII messages.

     (Contributed by Nikos Tsinoremas)


     Walter Sidler (E.T.H., Zuerich) described how he and coworkers have

successfully reconstituted the rod core complex, (alpha-beta)6PCתLRC29.5ת

(alpha-beta)3APתLC8.9 from Mastigocladus laminosus. This reconstitution

required using linker polypeptide LRC29.5 which had been overexpressed in E.

coli. The authors suggested that this requirement might result from

proteolysis of LRC29.5 in preparations from M. laminosus. Hopefully this

reconstituted complex will form beautiful crystals suitable for X-ray

crystallography! The core-membrane linker (LCM) functions to organize the

allophycocyanin trimers within the core complex and thus determines the

overall shape of the phycobilisome. Core complexes with two cylinders

(Synechococcus PCC 6301) and three cylinders (Synechococcus PCC 7002) have

been previously characterized. 

     Axel Ducret (E.T.H., Zuerich) showed electron micrographs of core

complexes reconstituted from Anabaena PCC 7120. In his interpretation of the

data, a core complex consists of three cylinders plus an additional

allophycocyanin (AP) complex attached to each side of the top cylinder (i.e.

a three-and-two-halves-cylinder core complex). I wonder if a five cylinder

phycobilisome might occur in another species. 

     Samuel Beale (Brown University) reported evidence, derived from work on

Cyanidium caldarium ("cyanobacterium", honoris causa?), that supports an

interesting pathway of phycobilin synthesis. If this pathway is present

generally in cyanobacteria, then it should be possible to find

phycoerythrobilin in all cyanobacteria regardless of whether phycoerythrin

is synthesized. The pathway begins with the conversion of protoheme to

biliverdin IXalpha by heme oxygenase. Two enzymes are required to convert

biliverdin IXalpha to (3Z)-phycoerythrobilin. 15,16-dihydrobiliverdin IXalpha

is the intermediate in this conversion.  The two enzymes each catalyse a

two-electron reduction, and require NADPH and ferredoxin. The isomerization

of (3Z)-phycoerythrobilin to (3Z)-phycocyanobilin requires a specific

isomerase. Z-to-E isomerizations of these latter two bilins is enzymatic and

requires glutathione. 

     Craig Fairchild (U.C. Berkeley) described his work two proteins, CpcE and

CpcF, required for the proper attachment of phycocyanobilin attachment to the

alpha subunit of phycocyanin (PC). These polypeptides were purified from

overexpressing E. coli and shown to associate with each other. The complex

(CpcEF) catalyses not only bilin attachment but also the transfer of bilin

from one alpha subunit to another. CpcEF also associates with PC and quenches

fluorescence emission.

     The last three speakers described work on chromatic adaptation in

Fremyella diplosiphon. Michael Schaefer (University of Missouri, Kansas City)

described two mutants which fail to respond to red light. He and coworkers

at the Carnegie Institution, Stanford have complemented these mutants using

a mobilizable plasmid library. The complementing gene, designated rcaC, shows

strong identity to phoP, a regulatory protein involved in phosphate

metabolism in Bacillus subtilis. The exact role of rcaC in chromatic

adaptation is presently unknown. 

     Nancy Federspiel and colleagues (University of Idaho, Moscow) reported

progress on in vivo and in vitro footprinting of the promoter of the cpeBA

operon (cpeBA encodes the beta and alpha subunits of phycoerythrin). Using

dimethyl sulfate, they identified two G residues within the promoter that are

protected in DNA isolated from cultures grown in either red or green light.

They concluded, therefore, that the protecting factor is bound to the

promoter, independent of light quality. This conclusion differs from that

drawn by Nicole Tandeau de Marsac (Institut Pasteur) and coworkers, working

with the similar strain, Calothrix PCC 7601. They found that the same

residues were protected only in green light. 

     John Cobley (University of San Francisco) presented the recent work from

his laboratory concerning a mutant, F. diplosiphon SF48, that fails in green

light to assemble phycoerythrin into the phycobilisome.  Using a mobilizable

cosmid library it was possible to complement this mutant and thereby clone

the complementing gene, which has been named cpeF. cpeF has more than 30%

sequence identity to both mpeV and mpeU, genes from Synechococcus WH8020.

CpeF most probably attaches a phycoerythrobilin to a specific cysteine in

phycoerythrin. It will be particularly interesting to see if the expression

of cpeF in F. diplosiphon is dependent on green light. 

     (Contributed by John Cobley)

              Nitrogen Metabolism and Heterocyst Differentiation

Nitrogen Metabolism:

     In Synechococcus PCC 7942, the genes involved in nitrate assimilation are

organized into a cluster, nirA-nrtABCD-narB, and expressed as an operon.

Tetsuo Omata (Nagoya University) reported the presence of two

ammonium-repressible genes in the region upstream of nirA. One open reading

frame (orf349) is required for the expression of maximal activity of nirA.

A mutant affected in the other (orf309) exhibits normal levels of nitrate

reductase and nitrite reductase activities but nonetheless grows slowly with

nitrate or nitrite as the nitrogen source. The predicted protein sequence

encoded by orf309 is similar to that of transcriptional regulators of the

LysR family. 

     Enrique Flores (Universidad de Sevilla) talked about a second regulatory

protein, NtcA, which is involved in transcriptional activation of ammonium

repressible genes. NtcA is found in a variety of unicellular, filamentous,

and heterocystous cyanobacteria. There is considerable sequence similarity

in the three ntcA genes that have been sequenced (from Synechococcus

PCC 7942, Synechocystis PCC 6803 and Anabaena PCC 7120), particularly in a

conserved helix-turn-helix motif. Footprinting studies indicate a consensus

binding sequence of GTA..N8..TACA, found with only minor variations upstream

from a number of nitrogen-regulated genes from different cyanobacteria. These

genes include nirA, glnA, hetA, hetR, patA, and ntcA itself.

     T.S. Ramasubramanian (Texas A&M University) reported on the

characterization of a gene (bifA) of Anabaena PCC 7120 that is evidently

identical to ntcA (although the identification of the two genes were by

wholly different approaches). Analysis of the binding of BifA to glnA, xisA,

and rbcL upstream sequences yielded a consensus recognition sequence of

TGT..N9-10..ACA, very close to the sequence obtained by the Seville group.

BifA is present in both vegetative cells and heterocysts. A mutant in which

bifA had been insertionally inactivated failed to grow on N2 or nitrate.

     Cyanothece BH68, a unicellular cyanobacterium showcased by Milagros Colon-

Lopez (Purdue University), exhibits the ability to fix nitrogen in the

presence of oxygen. When grown with an alternating light/dark cycle, N2-

fixation is restricted to the dark period and reaches peak activity at a time

coinciding with maximal respiratory activity. In a like fashion,

photosynthetic O2 evolution is confined to the light period, peaking 4-6 h

after the dark/light transition. The periodicity of N2-fixation is retained

when growth is shifted to continuous light. Richard Bradley (State University

of New York, Binghamton) suggested that Cyanothece may employ covalent

modification of nitrogenase as a form of post-translational control to

regulate nitrogenase activity. Western blot experiments using antibodies

directed against the Fe-subunit of nitrogenase revealed a band migrating at

38-kDa under conditions of aerobic nitrogenase activity and one at 40 Kda

under conditions in which nitrogenase activity was absent. 


Heterocyst differentiation: 

     A number of talks and posters addressed the question of heterocyst

differentiation and patterned development. Francisco Leganes (Michigan State

University) sought a connection between the two developmental processes of

heterocyst and akinete differentiation. He isolated a number of mutants of

Nostoc ellipsosporum that are defective in the differentiation of both cell

types (and hence cannot fix nitrogen in the presence of air). The two

processes appear therefore to be related by a common mechanism. 

     Several groups have found genes turned on early in the response of

Anabaena PCC 7120 to nitrogen deprivation. Genes involved in nitrate

assimilation seem to be among the earliest induced, reported Yuping Cai

(Michigan State University). Bill Buikema (University of Chicago) passed on

news of a gene (pknA) encoding a eukaryotic-type serine/threonine protein

kinase, isolated from Anabaena by PCR. Transcripts of pknA begin to

accumulate 2.5 hr after nitrogen stepdown. Stephanie Curtis (North Carolina

State University) described the isolation of gnd, encoding 6-phosphogluconate

dehydrogenase. The gene has multiple transcripts, at least one of which

becomes more abundant at about 6 h after removal of fixed nitrogen from the


     HetR is a gene required for heterocyst formation, which, we were told by

Yuping Cai, is essential for the expression of several genes induced during

the course of differentiation. Most remarkably, extra copies of hetR in wild

type Anabaena produces multiple heterocysts. Francisca Fernandez-Pinas

(Michigan State University) showed that extra copies of a newly discovered

gene, hetP, also produces multiple heterocysts. Mutation in hetP appears like

hetR- strains: no fragmentation and little if any sign of differentiation. 

     Other genes were described that are involved in unusual patterns of

heterocysts. Bill Buikema described patB, a gene induced 3 h after nitrogen

stepdown and whose predicted product has a DNA-binding motif in its carboxy

terminus. A mutation in patB shows increased heterocyst frequency. Jim Golden

(Texas A&M University) told us about a mutant strain PFM1 that has a patB--

like phenotype. A cosmid clone 8E11 that suppresses this phenotype was

identified and was found to suppress heterocyst development in wild type

Anabaena. A small fragment from 8E11 containing a 1200-bp ORF was sufficient

in multicopy to mimic the effect of the entire cosmid, but weirdly enough,

fragments containing sequences adjacent to the 1200 bp ORF on a high copy

shuttle vector had the opposite effect: it induced the formation of

heterocysts, even in nitrate-containing medium. 

     Todd Black (Michigan State University) showed work that support the idea

that lipid biosynthesis may be involved in heterocyst differentiation. A Het-

mutant was obtained by transposon mutagenesis, and sequences flanking the

transposon insertion were found to define an ORF that resembles beta-ketoacyl

reductases, involved in the synthesis of fatty acids, polyketides, and

several other compounds. Upstream from the first ORF was a second, whose

predicted product has domains also found in polyketide synthetases.

Downstream, and on the opposite strand, is an ORF that shows homology to a

gene from Bacillus subtilis encoding a regulatory gene. Reminiscent of the

Texas A&M group's results with PFM1 (above), extra copies of the first ORF

in Anabaena results in a Het- phenotype, and extra copies of the 3' ORF

stimulates double heterocyst formation. Extra copies of both ORFs together

yielded a normal phenotype.

     Two DNA rearrangements are known to occur during heterocyst

differentiation in Anabaena PCC 7120. A third DNA rearrangement, which

involves the excision of about 11.5 kb of DNA, was reported by two groups.

Andrey Matveyev (Stockholm University) analyzed restriction patterns of

vegetative cell and heterocyst DNA by pulsed-field gel electrophoresis. Jim

Golden told how the same rearrangement was found in his laboratory during the

mapping of a cosmid isolated through the complementation of PFM1 (above).

     (Contributed by TS Ramasubramanian and Nick Mann)

                Redundancy and Response to Environmental Stress

     One major theme of the 1993 Cyanobacterial Workshop was how cyanobacteria

respond to environmental stresses. It was clear from the workshop that we are

reaching a better appreciation of the cyanobacterial machinery for sensing

and responding to particular stresses. For example, Jackie Collier (Stanford

University) described a genetic approach to understanding how cyanobacteria

break down phycobilisomes in response to nitrogen- or sulfur-deprivation and

described a newly isolated gene, designated nblA, which is required for this


     Within the general theme of stress responses, however, it kept coming up

that many cyanobacteria are not necessarily optimized for maximum growth

under optimal conditions. Many have instead opted for "redundancy" as a way

of insuring survival under many conditions. This was demonstrated at the

meeting by the reports of many proteins which apparently duplicate the

functions of other proteins for reasons that are not clear. For example,

Javier Florencio (Universidad de Sevilla) described how Synechocystis

PCC 6803 has not one, but two genes encoding glutamine synthetase (GS). The

second one, referred to as glnT, exhibits low homologies (about 10%) with

other cyanobacterial GS's and instead is more similar to the GS of

Bacteroides fragilis. Filamentous nitrogen-fixing cyanobacteria appear to

lack a homolog of the gene. Unlike glnA (encoding the conventional GS) glnT

is induced by removal of nitrate from the medium. Although this finding may

provide a clue as to the function of the second GS, the question remains: Why

have two GS proteins? 

     Several other examples of redundancy were presented. Lou Sherman (Purdue

University) demonstrated the presence of a gene (isiA) encoding an

alternative to the PS II protein CP43. The gene is induced under iron

limitation and expresses a protein with a shorter hydrophilic loop relative

to CP43. Golden (S) described the regulation of the three copies of psbA in

Synechococcus PCC 7942 under different light intensities and qualities. Georg

Schmetterer (Universitaet Wien) provided evidence for an alternative oxidase

pathway in Synechocystis PCC 6803. Terry Thiel (University of Missouri, St.

Louis) offered one of the best examples of "redundancy" in showing that

Anabaena variabilis ATCC 29413 has not only the canonical nif cluster of

nitrogen fixation genes, but also a set, nif2, for molybdenum-dependent

nitrogen fixation under anaerobic conditions, and a set, vnf, for

vanadium-dependent nitrogen fixation when molybdenum is not available. The

presentation of Martin Mulligan (Memorial University of Newfoundland) on the

recently discovered RNA binding proteins suggests that they are also found

in multiple copies. 

     Bianca Brahamsha (Scripps Institution of Oceanography) and Laurie Caslake

(Pennsylvania State University) presented evidence showing that Anabaena

PCC 7120 and Synechococcus PCC 7002 both have multiple RNA polymerase sigma

factors in addition to the housekeeping sigma factor, SigA. The known

alternative sigma factors of PCC 7120 (SigB and SigC) are induced under

nitrogen stress, and removal of nitrogen also appears to differentially

regulate the genes for alternative sigma factors from PCC 7002. 

     Aside from the obvious case of a vanadium-nitrogenase and some suggestions

of the importance of relative protein stability, we really don't know much

about the selective advantage of having these protein families. Perhaps

redundancy itself is of value or perhaps more of the reasons for these

duplicated functions will be presented at the next Cyanobacterial workshop.

     (Contributed by Brian Palenik)

                  Protein Phosphorylation (and other matters)

     Several presentations included evidence for the role of two component

sensory systems and protein phosphorylation in modulating the metabolism of

cells in response to a range of environmental transients. 

     Shivanthi Anandan (Texas A&M University) described a cloning strategy that

was aimed at isolating genes involved in a signal transduction pathway that

might regulate light responsive gene expression in Synechococcus sp.

PCC 7942. Regions conserved amongst response regulator sequences were used

to pull out two genes, which exhibited limited similarity to the bacterial

response regulators OmpR and PhoB. Experiments with a mutant carrying an

inactivated form of one of these genes suggested that it might be involved

in the sensing of low- to high-light transitions. David Laudenbach

(University of Western Ontario) reported, as part of a talk on the

acclimation of Synechococcus sp. PCC 7942 to sulfur stress, that genes

encoding a two component sensory system resided on the large 50-kb endogenous

plasmid. [Bianca Brahamsha, below, discusses N.M.'s own presentation, which

is certainly pertinent to the discussion here -- ed.]

     Sergey Shestakov (Moscow State University) described the characterization

of a herbicide (difunon) resistance gene from Synechocystis sp. PCC 6803,

which on sequence analysis turned out to be homologous to the phoR (histidine

protein kinase) gene of Bacillus subtilis. Michael Schaefer (University of

Missouri, Kansas City) related how a genomic fragment from Fremyella

diplosiphon encodes two histidine protein kinase genes as well as a

eukaryotic-type serine/threonine kinase. This genomic fragment complemented

a mutant of the blue mutant class that is defective in chromatic adaptation.

In keeping with this theme of protein phosphorylation, Martin Hagemann

(Universitaet Rostock) has found that this form of covalent modification

occurs during the response of Synechocystis sp. PCC 6803 to salt stress. 

     Not in keeping with this theme, but a very interesting talk nonetheless,

Georg Schmetterer (Universitaet Wien) presented evidence for a branched

pathway of terminal respiratory electron transport. Having cloned and

sequenced the genes coxABC coding for the three subunits of cytochrome c

oxidase from Synechocystis sp. PCC 6803, a mutant carrying an interrupted

coxA gene was constructed. No trace of cytochrome c oxidase activity could

be detected in either thylakoid or cytoplasmic membranes from the mutant, but

when O2 uptake was measured in the dark, the mutant was found to respire

almost normally, suggesting that Synechocystis sp PCC 6803 contains one or

more additional respiratory terminal oxidases that are cyanide-sensitive. An

interesting phenotype of the mutant is that it cannot grow chemohetero-

trophically, even with the brief pulses of light that permits such growth in

the wild-type strain.

     (Contributed by Nick Mann)

                            Miscellaneous Topics

     Carl Johnson (University of Tennessee) reported on work he and several

colleagues have done on circadian rhythms in Synechococcus PCC 7942. Using

lux fusions to the psbAI promoter, they monitored bioluminescence following

entrainment of the culture to light and dark cycles and found that expression

of the psbAI-lux fusion exhibited the criteria of circadian rhythms, namely,

persistence in constant conditions, phase resetting by light/dark signals,

and temperature compensation of the period. Furthermore, he described an

amazing apparatus that is capable of monitoring the bioluminescence of

isolated colonies on plates. Using this device to screen mutagenized

colonies, they have isolated three mutants: one that is completely

arrhythmic, a long period mutant, and a short period mutant. Once again,

prokaryotes provide a genetically manipulatable system to model a behavior

more associated with eukaryotes, and we look forward to future developments

in the molecular and genetic characterization of the clock. 

     For those of you who have marvelled at how a dried-out colony of Anabaena

PCC 7120 forgotten on an old dried out BG11 plate comes back to life when

placed in liquid, Pete Lammers (New Mexico State University) may have part

of the answer. Using antibodies against a consensus peptide found in

dehydrins, a family of desiccation proteins that accumulate in plants in

response to dehydration stress, his laboratory identified a 40-kd polypeptide

in Anabaena PCC 7120. This 40-kd polypeptide, which they call cyanodehydrin,

is induced by osmotic stress (sucrose, sorbitol, PEG). They have also found

putative cyanodehydrins in two other filamentous cyanobacteria: Calothrix

PCC 7601 and Nostoc PCC 7911. Although plant dehydrins accumulate in response

to dehydration caused by a variety of stresses, their function has not been

determined. It will now be possible to address such functional questions in

the genetically manipulatable Anabaena PCC 7120. 

     Marine group A Synechococcus were represented in two posters and a talk.

These phycoerythrin-containing unicellular cyanobacteria are abundant in the

oligotrophic open ocean and are thought to be responsible for 5 to 25% of

primary production. Their adaptive responses to nutrient limitation and other

stresses are of interest. John Rueter and others at Portland State University

are studying the interrelationship of iron-, light-, and nitrogen-limitation

in Synechococcus WH7803 grown in continuous culture. Nicholas Mann

(University of Warwick) described the response of Synechococcus WH7803 to

phosphate limitation. He and coworkers have isolated a gene, pstS, which is

induced by phosphate limitation. Its product is localized to the cell

envelope, and it shows 35% identity to the inducible periplasmic phosphate

binding protein of E. coli. The have also cloned from WH7803 genes encoding

homologs to proteins, PhoR and PhoB, that regulate the response of E. coli

to phosphate deprivation by means of a two component sensory system.

     Brian Palenik described the use of RNA polymerase sequence data (that

derived from a conserved portion of the cyanobacterial rpoC1 gene) to study

the evolution and ecology of marine Synechococcus and Prochlorococcus sp. He

also urged anyone interested in the evolution of cyanobacteria to include

Gloeobacter in her/his analyses, as members of the genus appear by both RNA

polymerase and 16S rRNA sequence data to be representatives of the oldest

known cyanobacterial lineage. 

     (Contributed by Bianca Brahamsha)



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Bergman B, Rai AN, Johansson, Soederbaeck E (1993). Cyanobacterial-plant

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                         TOXINS and NATURAL SUBSTANCES

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     (1993). The Isolation of Majusculamide-C from the Sponge Ptilocaulis

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            TOXINS and NATURAL SUBSTANCES (Physiological Effects)

Bagchi SN, Chauhan VS, Marwah JB (1993). Effect of an Antibiotic from

     Oscillatoria late-virens on Growth, Photosynthesis, and Toxicity of

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Claeyssens S, Chedeville A, Lavoinne A (1993). Inhibition of Protein

     Phosphatases Activates Glucose-6-Phosphatase in Isolated Rat Hepatocytes.

     FEBS Lett 315(1):7-10.

Conradt B, Shaw J, Vida T, Emr S, Wickner W (1992). Invitro Reactions of

     Vacuole Inheritance in Saccharomyces Cerevisiae [effect of microcystin-

     LR]. J Cell Biol 119(6):1469-1479.

Elder GH, Hunter PR, Codd GA (1993). Hazardous Freshwater Cyanobacteria

     (Blue-Green Algae). Lancet 341(8859):1519-1520.

Elsaadi O, Cameron AS (1993). Illness Associated with Blue-Green Algae. Med

     J Aust 158(11):792-793.

Katsuyama H, Morgan KG (1993). Mechanisms of Ca2+-Independent Contraction in

     Single Permeabilized Ferret Aorta Cells [effect of microcystin-LR]. Circ

     Res 72(3):651-657.

Kiviranta J (1992). Larvicidal effects of toxic cyanobacteria on yellow fever

     Mosquito, Aedes aegypti. Acta Pharm Fenn 101:105-109.

Kozikowski AP, Ma D, Pang YP, Shum P, Likic V, Mishra PK, Macura S, Basu A,

     Lazo JS, Ball RG(1993). Synthesis, Molecular Modeling, 2-D NMR, and

     Biological Evaluation of ILV Mimics as Potential Modulators of Protein

     Kinase C. J Am Chem Soc 115(10):3957-3965.

Lau AF, Siedlecki J, Anleitner J, Patterson GML, Caplan FR, Moore RE (1993).

     Inhibition of Reverse Transcriptase Activity by Extracts of Cultured

     Blue-Green Algae (Cyanophyta). Planta Med 59(2):148-151.

Mellgren G, Vintermyr OK, Boe R, Doskeland SO (1993). Hepatocyte DNA

     Replication Is Abolished by Inhibitors Selecting Protein Phosphatase-2A

     Rather Than Phosphatase-1. Exp Cell Res 205(2):293-301.

Ohta T, Nishiwaki R, Yatsunami J, Komori A, Suganuma M, Fujiki H (1992).

     Hyperphosphorylation of Cytokeratins 8 and 18 by Microcystin-LR, a New

     Liver Tumor Promoter, in Primary Cultured Rat Hepatocytes. Carcinogenesis


Thompson WL, Pace JG (1992). Substances That Protect Cultured Hepatocytes

     from the Toxic Effects of Microcystin-LR. Toxicol In Vitro 6(6):579.

Vintermyr OK, Gjertsen BT, Lanotte M, Doskeland SO (1993). Microinjected

     Catalytic Subunit of cAMP-Dependent Protein Kinase Induces Apoptosis in

     Myeloid Leukemia (IPC-81) Cells. Exp Cell Res 206(1):157-161.

                          PHYSIOLOGY and METABOLISM

Aiba H, Nagaya M, Mizuno T (1993). Sensor and Regulator Proteins from the

     Cyanobacterium Synechococcus Species PCC 7942 That Belong to the Bacterial

     Signal-Transduction Protein Families - Implication in the Adaptive

     Response to Phosphate Limitation. Mol Microbiol 8(1):81-91.

Bonting CFC, Kortstee GJJ, Boekestein A, Zehnder AJB (1993). The Elemental

     Composition Dynamics of Large Polyphosphate Granules in Acinetobacter

     Strain 210A. Arch Microbiol 159(5):428-434.

Hippesanwald S (1993). Impact of Freeze Substitution on Biological Electron

     Microscopy. Microsc Res Technique 24(5):400-422.

Kohn C, Schumann J (1993). Nucleotide Sequence and Homology Comparison of two

     Genes of the Sulfate Transport Operon from the Cyanobacterium

     Synechocystis Sp PCC 6803. Plant Mol Biol 21(2):409-412.

Ohmori K, Hirose M, Ohmori M (1993). An Increase in the Intracellular

     Concentration of cAMP Triggers Formation of an Algal Mat by the

     Cyanobacterium Spirulina platensis. Plant Cell Physiol 34(1):169-171.

Potts M, Sun H, Mockaitis K, Kennelly PJ, Reed D, Tonks NK (1993). A

     Protein-Tyrosine/Serine Phosphatase Encoded by the Genome of the

     Cyanobacterium Nostoc commune UTEX 584. J Biol Chem 268(11):7632-7635.

Thomsen JK, Cox RP (1993). Upper Temperature Limits for Growth and

     Diazotrophy in the Thermophilic Cyanobacterium HTF Chlorogloeopsis. Arch

     Microbiol 159(5):423-427.

                        LIPIDS and TEMPERATURE TOLERANCE

Los D, Horvath I, Vigh L, Murata N (1993). The Temperature-Dependent

     Expression of the Desaturase Gene desA in Synechocystis PCC 6803. FEBS

     Lett 318(1):57-60.

Merrano A (1992). Purification, Characterization and Function of

     Dihydrolipoamide Dehydrogenase from the Cyanobacterium Anabaena Sp Strain

     PCC 7119. Biochem J DEC 15;288( Part 3):823-830.

Nishiyama Y, Kovacs E, Lee CB, Hayashi H, Watanabe T, Murata N (1993).

     Photosynthetic Adaptation to High Temperature Associated with Thylakoid

     Membranes of Synechococcus PCC 7002. Plant Cell Physiol 34(2):337-343.

Quoc KP, Dubacq JP, Justin AM, Demandre C, Mazliak P (1993). Biosynthesis of

     Eukaryotic Lipid Molecular Species by the Cyanobacterium Spirulina

     platensis. Biochim Biophys Acta 1168(1):94-99.

Reddy AS, Nuccio ML, Gross LM, Thomas TL (1993). Isolation of a

     Delta-6-Desaturase Gene from the Cyanobacterium Synechocystis Sp Strain

     PCC 6803 by Gain-of-Function Expression in Anabaena Sp Strain PCC 7120.

     Plant Mol Biol 22(2):293-300.

Ritter D, Yopp JH (1993). Plasma Membrane Lipid Composition of the Halophilic

     Cyanobacterium Aphanothece halophytica. Arch Microbiol 159(5):435-439.

Stern N, Tietz A (1993). Octadecatetraenoate Synthesis in the Unicellular

     Alga Isochrysis galbana - Studies with Intact and Broken Chloroplasts.

     Biochim Biophys Acta 1167(3):248-256.

Torok Z, Szalontai B, Joo F, Wistrom CA, Vigh L (1993). Homogeneous Catalytic

     Deuteration of Fatty Acyl Chains as a Tool to Detect Lipid Phase

     Transitions in Specific Membrane Domains - A Fourier Transform Infrared

     Spectroscopic Study. Biochem Biophys Res Commun 192(2):518-524.

Wada H, Schmidt H, Heinz E, Murata N (1993). Invitro Ferredoxin-Dependent

     Desaturation of Fatty Acids in Cyanobacterial Thylakoid Membranes. J

     Bacteriol 175(2):544-547.


Broun II, Gorbik GP, Mirochnik OY (1992). Light-Induced Na+-Dependent H+

     Uptake by the Cyanobacterium Synechocystis PCC 6803 - Detection of a

     Mutant Strain Lacking Na+-Dependent Resistance to Protonophores.

     Biochemistry-Engl Tr 57(10):1100-1103.

Fernandes TA, Iyer V, Apte K (1993). Differential Responses of

     Nitrogen-Fixing Cyanobacteria to Salinity and Osmotic Stresses. Appl

     Environ Microbiol 59(3):899-904.

Lippert K, Galinski EA, Truper HG (1993). Biosynthesis and Function of

     Trehalose in Ectothiorhodospira Halochloris. Anton Leeuwenhoek Int J Gen

     M 63(1):85-91.

Mamedov M, Hayashi H, Murata N (1993). Effects of Glycinebetaine and

     Unsaturation of Membrane Lipids on Heat Stability of Photosynthetic

     Electron Transport and Phosphorylation Reactions in Synechocystis

     PCC 6803. Biochim Biophys Acta 1142(1-2):1-5.

Valiente EF, Avendano MD (1993). Sodium-Stimulation of Phosphate Uptake in

     the Cyanobacterium Anabaena PCC 7119. Plant Cell Physiol 34(2):201-207.

Bhunia AK, Roy D, Banerjee SK (1993). Carbaryl-Induced Effects on Glutathione

     Content, Glutathione Reductase and Superoxide Dismutase Activity of the

     Cyanobacterium Nostoc muscorum. Lett Appl Microbiol 16(1):10-13.

Chang C, Sibley TH (1993). Accumulation and Transfer of Copper by Oocystis

     pusilla. Bull Environ Contam Toxicol 50(5):689-695.

Demarsac NT, Houmard J (1993). Adaptation of Cyanobacteria to Environmental

     Stimuli - New Steps Towards Molecular Mechanisms. FEMS Microbiol Rev


Dubinin AV, Zastrizhnaya OM, Gusev MV (1992). Hydrogen Peroxide Production

     by the Halophilic Cyanobacterium Microcoleus Chthonoplastes.

     Microbiology-Engl Tr 61(3):261-266.

Garnham GW, Codd GA, Gadd GM (1993). Uptake of cobalt and cesium by

     microalgal- and cyanobacterial-clay mixtures. Microb Ecol 25:71-82.

Gupta A, Morby AP, Turner JS, Whitton BA, Robinson NJ (1993). Deletion Within

     the Metallothionein Locus of Cadmium-Tolerant Synechococcus PCC 6301

     Involving a Highly Iterated Palindrome (HIP1). Mol Microbiol 7(2):189-195.

Huckle JW, Morby AP, Turner JS, Robinson NJ (1993). Isolation of a

     Prokaryotic Metallothionein Locus and Analysis of Transcriptional Control

     by Trace Metal Ions. Mol Microbiol 7(2):177-187.

Ivanov AY, Fomchenkov VM, Khasanova LA, Kuramshina ZM, Sadikov MM (1992).

     Effect of Heavy Metal Ions on the Electrophysical Properties of Anacystis

     nidulans and Escherichia coli. Microbiology-Engl Tr 61(3):319-326.

Kozitskaya VN, Komarenko EI, Chernyshova NA (1992). Structural and Functional

     Peculiarities of Cyanobacterium Microcystis aeruginosa Depending on the

     Effect of the Water Medium's Active Reaction. Microbiology-Engl Tr


Lee LH, Lustigman B, Maccari J (1993). Effect of Copper on the Growth of

     Anacystis nidulans. Bull Environ Contam Toxicol 50(4):600-607.

Lehel C, Gombos Z, Torok Z, Vigh L (1993). Growth Temperature Modulates

     Thermotolerance and Heat Shock Response of

     Cyanobacterium Synechocystis PCC 6803. Plant Physiol Biochem 31(1):81-88.

Michel KP, Pistorius EK (1992). Isolation of a Photosystem-II Associated

     36-kDa Polypeptide and an Iron-Stress 34-kDa Polypeptide from Thylakoid

     Membranes of the Cyanobacterium Synechococcus PCC 6301 Grown Under Mild

     Iron Deficiency. Z Naturforsch C 47(11-12):867-874.

Morby AP, Turner JS, Huckle JW, Robinson NJ (1993). SmtB Is a Metal-Dependent

     Repressor of the Cyanobacterial Metallothionein Gene smtA - Identification

     of a Zn Inhibited DNA-Protein Complex. Nucleic Acids Res 21(4):921-925.

Murthy SDS, Mohanty P (1993). Time-Dependent Alterations in the Antenna

     Pigment Protein Complex by Mercury Ions in the Cyanobacterium Spirulina

     platensis. Biometals SPR;6(1):45-48.

Pandey PK, Singh SP (1993). Hg2+ Uptake in a Cyanobacterium. Curr Microbiol


Rachlin JW, Grosso A (1993). The Growth Response of the Green Alga Chlorella

     vulgaris to Combined Divalent Cation Exposure. Arch Environ Contam Toxicol


Shuttleworth KL, Unz RF (1993). Sorption of Heavy Metals to the Filamentous

     Bacterium Thiothrix strain A1. Appl Environ Microbiol 59(5):1274-1282.

Singh AL, Asthana RK, Srivastava SC, Singh SP (1992). Nickel Uptake and Its

     Localization in a Cyanobacterium. FEMS Microbiol Lett 1;99(2-3):165-168.

Verma SK, Singh RK, Singh SP (1993). Copper Toxicity and Phosphate

     Utilization in the Cyanobacterium Nostoc calcicola. Bull Environ Contam

     Toxicol 50(2):192-198.


Coronil T, Lara C, Guerrero MG (1993). Shift in Carbon Flow and Stimulation

     of Amino Acid Turnover Induced by Nitrate and Ammonium Assimilation in

     Anacystis nidulans. Planta 189(3):461-467.

Elmorjani K, Liotenberg S, Houmard J, Demarsac NT (1992). Molecular

     Characterization of the Gene Encoding Glutamine Synthetase in the

     Cyanobacterium Calothrix Sp PCC 7601. Biochem Biophys Res Commun DEC


Jansson E, Martel A, Lindblad P (1993). Ornithine Cycle in Nostoc PCC 73102

     - Stimulation of In vitro Ornithine Carbamoyl Transferase Activity by

     Addition of Arginine. Curr Microbiol 26(2):75-78.

Luque I, Flores E, Herrero A (1993). Nitrite Reductase Gene from

     Synechococcus Sp PCC 7942 - Homology Between Cyanobacterial and

     Higher-Plant Nitrite Reductases. Plant Mol Biol 21(6):1201-1205.

Marco E, Orus MI (1993). Trichlorfon-Induced Inhibition of Nitrate and

     Ammonium Uptake in Cyanobacteria. J Exp Bot 44(259):501-508.

Martel A, Jansson E, Garciareina G, Lindblad P (1993). Ornithine Cycle in

     Nostoc PCC 73102 - Arginase, OCT and Arginine Deiminase, and the Effects

     of Addition of External Arginine, Ornithine, or Citrulline. Arch Microbiol


Murphy ST, Jackman DM, Mulligan ME (1993). Cloning and Nucleotide Sequence

     of the Gene for Dinitrogenase Reductase (nifH) from the Heterocyst-Forming

     Cyanobacterium Anabaena Sp L31. Biochim Biophys Acta 1171(3):337-340.

Ohki K, Zehr JP, Fujita Y (1992). Regulation of Nitrogenase Activity in

     Relation to the Light-Dark Regime in the Filamentous Non-Heterocystous

     Cyanobacterium Trichodesmium Sp NIBB 1067. J Gen Microbiol 138( Part


Omata T, Andriesse X, Hirano A (1993). Identification and Characterization

     of a Gene Cluster Involved in Nitrate Transport in the Cyanobacterium

     Synechococcus sp. PCC 7942. Mol Gen Genet 236(2-3):193-202.

Prufert-Bebout L, Paerl HW, Lassen C (1993). Growth, Nitrogen Fixation, and

     Spectral Attenuation in Cultivated Trichodesmium Species. Appl Environ

     Microbiol 59(5):1367-1375.

Singh S (1993). Role of Glutamine Synthetase, Glutamine and NH4+ in the

     Regulation of Glutamine Uptake in the Cyanobacterium Anabaena cycadeae.

     J Gen Appl Microbiol Tokyo 39(1):57-64.

Singh S (1993). Regulation of Glutamate Metabolism in the Cyanobiont Nostoc

     anth by Nitrogen Sources. J Basic Microbiol 33(1):41-45.

Singh S (1993). Role of Glutamine Synthetase Activity in the Uptake and

     Metabolism of Arginine and Proline in the Cyanobacterium Anabaena

     cycadeae. FEMS Microbiol Lett 106(3):335-340.

Singh S, Chakravarty D, Singh HN (1993). Mutational Replacement of Molybdenum

     by Vanadium in Assimilation of N2 or NO3- as Nitrogen Source in the

     Cyanobacterium Nostoc muscorum. Biochem Mol Biol Int 29(6):1083-1093.

Smith PT, King AD, Goodman N (1993). Isolation and Characterization of Urease

     from Aspergillus niger. J Gen Microbiol 139( Part 5):957-962.

Srivastava R, Amla DV (1993). Physiological and Biochemical Analysis of the

     Glutamine Synthetase-Impaired Mutants of the Nitrogen-Fixing

     Cyanobacterium Nostoc muscorum. Curr Microbiol 26(4):205-215.

Thomas SP, Shanmugasundaram S (1992). Amino Acid Overproduction by Analog

     Resistant Mutants of the Nitrogen Fixing Cyanobacterium Anabaena sp 287.

     Appl Biochem Biotechnol 37(2):111-121.

Wagner SJ, Thomas SP, Kaufman RI, Nixon BT, Stevens SE (1993). The glnA Gene

     of the Cyanobacterium Agmenellum quadruplicatum PR-6 Is Nonessential for

     Ammonium Assimilation. J Bacteriol 175(3):604-612.

Bebout BM, Fitzpatrick MW, Paerl HW (1993). Identification of the Sources of

     Energy for Nitrogen Fixation and Physiological Characterization of

     Nitrogen-Fixing Members of a Marine Microbial Mat Community. Appl Environ

     Microbiol 59(5):1495-1503.

Reddy KJ, Haskell JB, Sherman DM, Sherman LA (1993). Unicellular, Aerobic

     Nitrogen-Fixing Cyanobacteria of the Genus Cyanothece. J Bacteriol


Yakunin AF, Troshina OY, Jha M, Gogotov IN (1992). Effect of Ammonium on

     Nitrogenase Activity in the Heterocystous Cyanobacterium Anabaena

     variabilis. Microbiology-Engl Tr 61(3):256-260.

Zehr JP, Wyman M, Miller V, Duguay L, Capone DG (1993). Modification of the

     Fe Proteinthi of Nitrogenase in Natural Populations of Trichodesmium

     thiebautii. Appl Environ Microbiol 59(3):669-676.

                       DIFFERENTIATION and HYDROGENASE

Black TA, Cai Y, Wolk CP (1993). Spatial expression and autoregulation of

     hetR, a gene involved in the control of heterocyst development in

     Anabaena. Molec Microbiol 9:77-84.

Buikema WJ, Haselkorn R (1993). Molecular Genetics of Cyanobacterial

     Development. Annu Rev Plant Physiol 4433-52.

Campbell D, Houmard J, Tandeau de Marsac N (1993). Electron Transport

     Regulates Cellular Differentiation in the Filamentous Cyanobacterium

     Calothrix. Plant Cell 5(4):451-463.

Haselkorn R (1992). Developmentally Regulated Gene Rearrangements in

     Prokaryotes. Annu Rev Genet 26113-130.

Kaiser D, Losick R (1993). How and Why Bacteria Talk to Each Other. Cell


Kangatharalingam N, Priscu JC, Paerl HW (1992). Heterocyst Envelope

     Thickness, Heterocyst Frequency and Nitrogenase Activity in Anabaena flos

     aquae - Influence of Exogenous Oxygen Tension. J Gen Microbiol


Liang JH, Scappino L, Haselkorn R (1993). The patB Gene Product, Required for

     Growth of the Cyanobacterium Anabaena Sp Strain PCC 7120 Under

     Nitrogen-Limiting Conditions, Contains Ferredoxin and Helix-Turn-Helix

     Domains. J Bacteriol 175(6):1697-1704.

Soriente A, Gambacorta A, Trincone A, Sili C, Vincenzini M, Sodano G (1993).

     Heterocyst Glycolipids of the Cyanobacterium Cyanospira rippkae.

     Phytochemistry 33(2):393-396.

Wolk CP, Elhai J, Kuritz T, Holland D (1993). Amplified Expression of a

     Transcriptional Pattern Formed During Development of Anabaena. Mol

     Microbiol 7(3):441-445.

Sarkar S, Pandey KD, Kashyap AK (1992). Simultaneous Photoproduction of

     Hydrogen and Ammonia by a Non-Heterocystous Cyanobacterium Plectonema

     boryanum. J Gen Appl Microbiol Tokyo 38(5):407-415.

Serebryakova LT, Zorin NA, Gogotov IN (1992). Hydrogenase Activity of

     Filamentous Cyanobacteria. Microbiology-Engl Tr 61(2):107-112.

                            CARBON METABOLISM

De Philippis R, Ena A, Guastini M, Sili C, Vincenzini M (1992). Factors

     Affecting Poly-beta-Hydroxybutyrate Accumulation in Cyanobacteria and in

     Purple Non-Sulfur Bacteria. FEMS Microbiol Rev 103(2-4):187-194.

Grotjohann N, Schneider G, Kowallik W (1993). Different Forms of Fructose

     1,6-Bisphosphatase in Chlorella. Z Naturforsch C 48(1-2):22-27.

Guy RD, Fogel ML, Berry JA (1993). Photosynthetic Fractionation of the Stable

     Isotopes of Oxygen and Carbon. Plant Physiol 101(1):37-47.

Larimer FW, Soper TS (1993). Overproduction of Anabaena 7120

     Ribulose-Bisphosphate Carboxylase/Oxygenase in Escherichia coli. Gene


Lee GJ, McDonald KA, McFadden BA (1993). Leucine 332 influences the CO2/O2

     specificity factor of ribulose-1,5-bisphosphate carboxylase/oxygenase from

     Anacystis nidulans. Prot Sci 2:1147-1154.

Li LA, Gibson JL, Tabita FR (1993). The Rubisco Activase (rca) Gene Is

     Located Downstream from rbcS in Anabaena Sp Strain CA and Is Detected in

     Other Anabaena Nostoc Strains. Plant Mol Biol 21(5):753-764.

Luinenburg I, Coleman JR (1993). Expression of Escherichia coli

     Phosphoenolpyruvate Carboxylase in a Cyanobacterium - Functional

     Complementation of Synechococcus PCC 7942 ppc. Plant Physiol


Marco E, Ohad N, Schwarz R, Liemanhurwitz J, Gabay C, Kaplan A (1993). High

     CO2 Concentration Alleviates the Block in Photosynthetic Electron

     Transport in an ndhB-Inactivated Mutant of Synechococcus Sp PCC 7942.

     Plant Physiol 101(3):1047-1053.

Price GD, Howitt SM, Harrison K, Badger MR (1993). Analysis of a Genomic DNA

     Region from the Cyanobacterium Synechococcus Sp Strain PCC 7942 Involved

     in Carboxysome Assembly and Function. J Bacteriol 175(10):2871-2879.

Read BA, Tabita FR (1992). Amino acid substitutions in the small subunit of

     ribulose-1,5-bisphosphate carboxylase/oxygenase that influence catalytic

     activity of the holoenzyme. Biochem 31:519-525.

Read BA, Tabita FR (1992). A hybrid ribulosebisphosphate

     carboxylase/oxygenase enzyme exhibiting a substantial increase in

     substrate specificity factor. Biochem 31:5553-5560.

Schwarz R, Liemanhurwitz J, Hassidim M, Kaplan A (1992). Phenotypic

     Complementation of High CO2-Requiring Mutants of the Cyanobacterium

     Synechococcus Sp Strain PCC 7942 by Inosine 5'-Monophosphate. Plant

     Physiol 100(4):1987-1993.

Stal LJ (1992). Poly(hydroxyalkanoate) in Cyanobacteria - An Overview. FEMS

     Microbiol Rev 103(2-4):169-180.


Bader KP, Schmid GH, Ruyters G, Kowallik W (1992). Blue Light Enhanced

     Respiratory Activity Under Photosynthetic Conditions in Chlorella - A Mass

     Spectrometric Analysis. Z Naturforsch C 47(11-12):881-888.

Foguel D, Chaloub RM, Silva JL, Crofts AR, Weber G (1992). Pressure and Low

     Temperature Effects on the Fluorescence Emission Spectra and Lifetimes of

     the Photosynthetic Components of Cyanobacteria. Biophys J 63(6):1613-1622.

Greer DH, Laing WA, Woolley DJ (1993). The Effect of Chloramphenicol on

     Photoinhibition of Photosynthesis and Its Recovery in Intact Kiwifruit

     (Actinidia deliciosa) Leaves. Aust J Plant Physiol 20(1):33-43.

Kim JH, Glick RE, Melis A (1993). Dynamics of Photosystem Stoichiometry

     Adjustment by Light Quality in Chloroplasts. Plant Physiol 102(1):181-190.

Kondo T, Strayer CA, Kulkarni RD, Taylor W, Ishiura M, Golden SS, Johnson CH

     (1993). Circadian rhythms in prokaryotes: luciferase as a reporter of

     circadian gene expression in cyanobacteria. Proc Natl Acad Sci USA.

Lapointe L, Huner NPA, Leblanc RM, Carpentier R (1993). Possible

     Photoacoustic Detection of Cyclic Electron Transport Around Photosystem II

     in Photoinhibited Thylakoid Preparations. Biochim Biophys Acta


Mi HL, Endo T, Schreiber U, Asada K (1992). Donation of Electrons from

     Cytosolic Components to the Intersystem Chain in the Cyanobacterium

     Synechococcus Sp PCC 7002 as Determined by the Reduction of P700+. Plant

     Cell Physiol 33(8):1099-1105.

Mi HL, Endo T, Schreiber U, Ogawa T, Asada K (1992). Electron Donation from

     Cyclic and Respiratory Flows to the Photosynthetic Intersystem Chain Is

     Mediated by Pyridine Nucleotide Dehydrogenase in the Cyanobacterium

     Synechocystis PCC 6803. Plant Cell Physiol 33(8):1233-1237.

Rudiger W (1992). Events in the Phytochrome Molecule After Irradiation.

     Photochem Photobiol 56(5):803-809.

                                 PHOTOSYSTEM I

Bouyoub A, Vernotte C, Astier C (1993). Functional Analysis of the two

     Homologous psbA Gene Copies in Synechocystis PCC 6714 and PCC 6803. Plant

     Mol Biol 21(2):249-258.

Chitnis VP, Xu Q, Yu L, Golbeck JH, Nakamoto H, Xie DL, Chitnis PR (1993).

     Targeted Inactivation of the Gene psaL Encoding a Subunit of Photosystem I

     of the Cyanobacterium Synechocystis Sp PCC 6803. J Biol Chem


Golbeck JH (1993). Shared Thematic Elements in Photochemical Reaction

     Centers. Proc Natl Acad Sci USA 90(5):1642-1646.

Guigliarelli B, Guillaussier J, More C, Setif P, Bottin H, Bertrand P (1993).

     Structural Organization of the Iron-Sulfur Centers in Synechocystis 6803

     Photosystem I - EPR Study of Oriented Thylakoid Membranes and Analysis of

     the Magnetic Interactions. J Biol Chem 268(2):900-908.

Hatanaka H, Sonoike K, Hirano M, Katoh S (1993). Small Subunits of

     Photosystem I Reaction Center Complexes from Synechococcus Elongatus.

     1. Is the psaF Gene Product Required for Oxidation of Cytochrome c553.

     Biochim Biophys Acta 1141(1):45-51.

Ikeuchi M, Sonoike K, Koike H, Pakrasi HB, Inoue Y (1992). A Novel 3.5-kDa

     Protein Component of Cyanobacterial Photosystem I Complexes. Plant Cell

     Physiol 33(8):1057-1063.

Kaurov YN, Aksyonova GE, Lovyagina ER, Veselova TV, Ivanov II (1992). On the

     Nature of Thermally-Induced Delayed Luminescence of Photosystem I from

     Thermophilic Cyanobacterial Membranes. Biol Membrany 9(8):845-857.

Krauss N, Hinrichs W, Witt I, Fromme P, Pritzkow W, Dauter Z, Betzel C,

     Wilson KS, Witt HT, Saenger W (1993). 3-Dimensional Structure of System I

     of Photosynthesis at 6 Angstrom Resolution. Nature 361(6410):326-331.

Mohamed A, Eriksson J, Osiewacz HD, Jansson C (1993). Differential Expression

     of the psbA Genes in the Cyanobacterium Synechocystis 6803. Mol Gen Genet


Muhlenhoff U, Haehnel W, Witt H, Herrmann RG (1993). Genes Encoding 11

     Subunits of Photosystem I from the Thermophilic Cyanobacterium

     Synechococcus Sp. Gene 127(1):71-78.

Rhiel E, Bryant DA (1993). Nucleotide Sequence of the psaE Gene of

     Cyanobacterium Synechococcus Sp PCC 6301. Plant Physiol 101(2):701-702.

Rousseau F, Setif P, Lagoutte B (1993). Evidence for the Involvement of PSI-E

     Subunit in the Reduction of Ferredoxin by Photosystem I. EMBO J


Smart LB, Mcintosh L (1993). Genetic Inactivation of the psaB Gene in

     Synechocystis Sp PCC 6803 Disrupts Assembly of Photosystem I. Plant Mol

     Biol 21(1):177-180.

Smart LB, Warren PV, Golbeck JH, Mcintosh L (1993). Mutational Analysis of

     the Structure and Biogenesis of the Photosystem I Reaction Center in the

     Cyanobacterium Synechocystis Sp PCC 6803. Proc Natl Acad Sci USA


Sonoike K, Hatanaka H, Katoh S (1993). Small Subunits of Photosystem I

     Reaction Center Complexes from Synechococcus Elongatus. 2. The psaE Gene

     Product Has a Role to Promote Interaction Between the Terminal Electron

     Acceptor and Ferredoxin. Biochim Biophys Acta 1141(1):52-57.

Tsiotis G, Nitschke W, Haase W, Michel H (1993). Purification and

     Crystallization of Photosystem I Complex from a Phycobilisome-Less Mutant

     of the Cyanobacterium Synechococcus PCC 7002. Photosynth Res


Turconi S, Schweitzer G, Holzwarth AR (1993). Temperature Dependence of

     Picosecond Fluorescence Kinetics of a Cyanobacterial Photosystem I

     Particle. Photochem Photobiol 57(1):113-119.

Vanderlee J, Bald D, Kwa SLS, Vangrondelle R, Rogner M, Dekker JP (1993).

     Steady-State Polarized Light Spectroscopy of Isolated Photosystem I

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Vanderstaay GWM, Boekema EJ, Dekker JP, Matthijs HCP (1993). Characterization

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                                 PHOTOSYSTEM II

Anbudurai PR, Pakrasi HB (1993). Mutational Analysis of the PsbL Protein of

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Astier C, Perewoska I, Picaud M, Kirilovsky D, Vernotte C (1993). Structural

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Boerner RJ, Bixby KA, Nguyen AP, Noren GH, Debus RJ, Barry BA (1993). Removal

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Boichenko VA, Klimov VV, Mayes SR, Barber J (1993). Characterization of the

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Foguel D, Chaloub RM (1993). Effects of the Alkaloid Gramine on the

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Haag E, Eatonrye JJ, Renger G, Vermaas WFJ (1993). Functionally Important

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Kless H, Orenshamir M, Ohad I, Edelman M, Vermaas W (1993). Protein

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Lind LK, Shukla VK, Nyhus KJ, Pakrasi HB (1993). Genetic and Immunological

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Lysenko ES, Ogarkova OA, Tarasov VA (1993). Localization of Cyanobacterium

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Maenpaa P, Kallio T, Mulo P, Salih G, Aro EM, Tyystjarvi E, Jansson C (1993).

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Mayes SR, Dubbs JM, Vass I, Hideg E, Nagy L, Barber J (1993). Further

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Miura K, Shimazu T, Motoki A, Kanai S, Hirano M, Katoh S (1993). Nucleotide

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Mor TS, Post AF, Ohad I (1993). The Manganese Stabilising Protein (MSP) of

     Prochlorothrix hollandica Is a Hydrophobic Membrane-Bound Protein. Biochim

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Pistorius EK (1993). The identity of the water oxidizing enzyme in

     photosystem II is still controversial. Physiol Plant 87:624-631.

Race HL, Gounaris K (1993). Identification of the PsbH Gene Product as a

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Satoh K, Kashino Y, Koike H (1993). Electron Transport from QA to

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Shen GZ, Eatonrye JJ, Vermaas WFJ (1993). Mutation of Histidine Residues in

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     Impairment of Light Energy Transfer. Biochemistry 32(19):5109-5115.

Shen JR, Inoue Y (1993). Binding and Functional Properties of 2 New Extrinsic

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Shutilova NI, Klimov VV, Antropova TM, Shnyrov VL (1992). Thermal

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Tang XS, Sivaraja M, Dismukes GC (1993). Protein and Substrate Coordination

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Tommos C, Davidsson L, Svensson B, Madsen C, Vermaas W, Styring S (1993).

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     Site-Directed Mutants of Synechocystis sp. PCC 6803 - Identification of

     Side Chains in the Immediate Vicinity of Tyrosine(D) on the D2 Protein.

     Biochemistry 32(20):5436-5441.

Vermaas W (1993). Molecular Biological Approaches to Analyze Photosystem II

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Apt KE, Grossman AR (1993). Genes Encoding Phycobilisome Linker Polypeptides

     on the Plastid Genome of Aglaothamnion neglectum (Rhodophyta). Photosynth

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Apt KE, Grossman AR (1993). Characterization and Transcript Analysis of the

     Major Phycobiliprotein Subunit Genes from Aglaothamnion neglectum

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Bhalerao RP, Lind LK, Persson CE, Gustafsson P (1993). Cloning of the

     Phycobilisome Rod Linker Genes from the Cyanobacterium Synechococcus Sp

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Capuano V, Thomas JC, Demarsac NT, Houmard J (1993). An In vivo Approach to

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     Phycobilisomes. J Biol Chem 268(11):8277-8283.

Delorimier R, Wilbanks SM, Glazer AN (1993). Genes of the R-Phycocyanin-II

     Locus of Marine Synechococcus spp and Comparison of Protein-Chromophore

     Interactions in Phycocyanins Differing in Bilin Composition. Plant Mol

     Biol 21(2):225-237.

Demidov AA, Borisov AY (1993). Numerical Modeling of Energy Migration in

     C-Phycocyanin of the Blue-Green Alga Agmenellum quadruplicatum. Biofizika


Demidov AA, Borisov AY (1993). Computer Simulation of Energy Migration in the

     C-Phycocyanin of the Blue-Green Algae Agmenellum quadruplicatum. Biophys

     J 64(5):1375-1384.

Dimagno L, Haselkorn R (1993). Isolation and Characterization of the Genes

     Encoding Allophycocyanin Subunits and 2 Linker Proteins from Synechocystis

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Ficner R, Lobeck K, Schmidt G, Huber R (1992). Isolation, Crystallization,

     Crystal Structure Analysis and Refinement of B-Phycoerythrin from the Red

     Alga Porphyridium Sordidum at 2.2 Angstrom Resolution. J Mol Biol


Gillbro T, Sharkov AV, Kryukov IV, Khoroshilov EV, Kryukov PG, Fischer R,

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     in C-Phycocyanin Trimers. Biochim Biophys Acta 1140(3):321-326.

Glauser M, Sidler W, Zuber H (1993). Isolation, Characterization and

     Reconstitution of Phycobiliprotein Rod-Core Linker Polypeptide Complexes

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Grossman AR, Schaefer MR, Chiang GG, Collier JL (1993). Environmental Effects

     on the Light Harvesting Complex of Cyanobacteria. J Bacteriol


Hucke M, Schweitzer G, Holzwarth AR, Sidler W, Zuber H (1993). Studies on

     Chromophore Coupling in Isolated Phycobiliproteins. 4. Femtosecond

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     Phycoerythrocyanin Complexes. Photochem Photobiol 57(1):76-80.

Kalla R, Bhalerao RP, Gustafsson P (1993). Regulation of Phycobilisome Rod

     Proteins and Messenger RNA at Different Light Intensities in the

     Cyanobacterium Synechococcus 6301. Gene 126(1):77-83.

Reuter W, Nickelreuter C (1993). Molecular Assembly of the Phycobilisomes

     from the Cyanobacterium Mastigocladus laminosus. J Photochem Photobiol

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Roell MK, Morse DE (1993). Organization, Expression and Nucleotide Sequence

     of the Operon Encoding R-Phycoerythrin alpha-Subunit and beta-Subunit from

     the Red Alga Polysiphonia Boldii. Plant Mol Biol 21(1):47-58.

Sai PSM, Siebzehnrubl S, Mahajan S, Scheer H (1993). Fluorescence and

     Circular Dichroism Studies on the Phycoerythrocyanins from the

     Cyanobacterium Westiellopsis Prolifica. Photochem Photobiol 57(1):71-75.

Scharnagl C, Fischer SF (1993). Reversible Photochemistry in the

     alpha-Subunit of Phycoerythrocyanin - Characterization of Chromophore and

     Protein by Molecular Dynamics and Quantum Chemical Calculations. Photochem

     Photobiol 57(1):63-70.

Schmidtgoff CM, Federspiel NA (1993). In vivo and In vitro Footprinting of

     a Light-Regulated Promoter in the Cyanobacterium Fremyella diplosiphon.

     J Bacteriol 175(6):1806-1813.

Schneider S, Prenzel CJ, Brehm G, Gedeck P, Sai PSM, Gottschalk L, Scheer H

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     Cyanobacteria Employing Resonance-Enhanced Coherent Anti-Stokes Raman

     Spectroscopy. Photochem Photobiol 57(1):56-62.

Sobczyk A, Schyns G, Demarsac NT, Houmard J (1993). Transduction of the Light

     Signal During Complementary Chromatic Adaptation in the Cyanobacterium

     Calothrix sp PCC 7601 - DNA-Binding Proteins and Modulation by

     Phosphorylation. EMBO J 12(3):997-1004.

Stadnichuk IN, Khokhlachev AV, Tikhonova YV (1993). Polypeptide

     gamma-Subunits of R-Phycoerythrin. J Photochem Photobiol B-Biol


Wehrmeyer W, Morschel E, Vogel K (1993). Core Substructure in Phycobilisomes

     of Red Algae. 2. The Central Part of the Tricylindrical Core - AP(CM) -

     A Constituent of Hemidiscoidal Phycobilisomes of Rhodella violacea. Eur

     J Cell Biol 60(1):203-209.

Westermann M, Reuter W, Schimek C, Wehrmeyer W (1993). Presence of Both

     Hemidiscoidal and Hemiellipsoidal Phycobilisomes in a Phormidium Species

     (Cyanobacteria). Z Naturforsch C 48(1-2):28-34.

Wilbanks SM, Glazer AN (1993). Rod Structure of a Phycoerythrin II-Containing

     Phycobilisome. 2. Complete Sequence and Bilin Attachment Site of a

     Phycoerythrin gamma-Subunit. J Biol Chem 268(2):1236-1241.

Wilbanks SM, Glazer AN (1993). Rod Structure of a Phycoerythrin II-Containing

     Phycobilisome. 1. Organization and Sequence of the Gene Cluster Encoding

     the Major Phycobiliprotein Rod Components in the Genome of Marine

     Synechococcus Sp WH8020. J Biol Chem 268(2):1226-1235.


Fraser PD, Linden H, Sandmann G (1993). Purification and Reactivation of

     Recombinant Synechococcus Phytoene Desaturase from an Overexpressing

     Strain of Escherichia coli. Biochem J 291( Part 3):687-692.

Fujita Y, Matsumoto H, Takahashi Y, Matsubara H (1993). Identification of a

     nifDK-Like Gene (ORF467) Involved in the Biosynthesis of Chlorophyll in

     the Cyanobacterium Plectonema boryanum. Plant Cell Physiol 34(2):305-314.

Garcia-Pichel F, Wingard CE, Castenholz RW (1993). Evidence regarding the UV

     sunscreen role of a mycosporine-like compound in the cyanobacterium

     Gloeocapsa sp. Appl Environ Microbiol 59:170-176.

Linden H, Vioque A, Sandmann G (1993). Isolation of a Carotenoid Biosynthesis

     Gene Coding for zeta-Carotene Desaturase from Anabaena PCC 7120 by

     Heterologous Complementation. FEMS Microbiol Lett 106(1):99-104.

Matsunaga T, Burgess JG, Yamada N, Komatsu K, Yoshida S, Wachi Y (1993). An

     Ultraviolet (UV-A) Absorbing Biopterin Glucoside from the Marine

     Planktonic Cyanobacterium Oscillatoria Sp. Appl Microbiol Biotechnol


Reddy KJ, Bullerjahn GS, Sherman LA (1993). Characteristics of

     Membrane-Associated Carotenoid-Binding Proteins in Cyanobacteria and

     Prochlorophytes. Carotenoids, Pt B 214 390-401.

Sandmann G, Fraser PD (1993). Differential Inhibition of Phytoene Desaturases

     from Diverse Origins and Analysis of Resistant Cyanobacterial Mutants. Z

     Naturforsch C 48(3-4):307-311.


Alge D, Peschek GA (1993). Characterization of a cta/CDE Operon-Like Genomic

     Region Encoding Subunits I-III of the Cytochrome c Oxidase of the

     Cyanobacterium Synechocystis PCC 6803. Biochem Mol Biol Int 29(3):511-525.

Alge D, Peschek GA (1993). Identification and Characterization of the ctaC

     (coxB) Gene as Part of an Operon Encoding Subunit-I, Subunit-II, and

     Subunit-III of the Cytochrome c Oxidase (Cytochrome aa3) in the

     Cyanobacterium Synechocystis PCC 6803. Biochem Biophys Res Commun


Howitt CA, Smith GD, Day DA (1993). Cyanide-Insensitive Oxygen Uptake and

     Pyridine Nucleotide Dehydrogenases in the Cyanobacterium Anabaena

     PCC 7120. Biochim Biophys Acta 1141(2-3):313-320.

Joliot P, Vermeglio A, Joliot A (1993). Supramolecular Membrane Protein

     Assemblies in Photosynthesis and Respiration. Biochim Biophys Acta


Kaprelyants AS, Kell DB (1993). The Use of 5-Cyano-2,3-Ditolyl Tetrazolium

     Chloride and Flow Cytometry for the Visualisation of Respiratory Activity

     in Individual Cells of Micrococcus Luteus. J Microbiol Meth 17(2):115-122.

Knaff DB (1993). The Cytochrome bc1 Complexes of Photosynthetic Purple

     Bacteria. Photosynth Res 35(2):117-133.

Mctavish H, Laquier F, Arciero D, Logan M, Mundfrom G, Fuchs J, Hooper AB

     (1993). Multiple Copies of Genes Coding for Electron Transport Proteins

     in the Bacterium Nitrosomonas Europaea.4.1 GENOME. J Bacteriol


Medina M, Diaz A, Hervas M, Navarro JA, Gomez-Moreno C, De La Rosa MA, Tollin

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     Anabaena PCC 7119 plastocyanin and cytochrome c6 photooxidation by

     photosystem I particles. Eur J Biochem 213:1133.

Bovy A, Devrieze G, Lugones L, Vanhorssen P, Vandenberg C, Borrias M,

     Weisbeek P (1993). Iron-Dependent Stability of the Ferredoxin I

     Transcripts from the Cyanobacterial Strains Synechococcus Species PCC 7942

     and Anabaena Species PCC 7937. Mol Microbiol 7(3):429-439.

Dai HP, Kentemich T, Schmitz K, Muller B, Bothe H (1992). Distribution of

     Thioredoxins in Heterocysts and Vegetative Cells of Cyanobacteria. J

     Photochem Photobiol B-Biol 16(3-4):285-295.

Hervas M, Navarro F, Navarro JA, Chavez S, Diaz A, Florencio FJ, Delarosa MA

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     Cyanobacterium and E. coli Transformed Cells Are Identical. FEBS Lett


Medina M, Diaz A, Hervas M, Navarro JA, Gomezmoreno C, Delarosa MA, Tollin

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     Anabaena PCC 7119 Plastocyanin and Cytochrome c6 Photooxidation by

     Photosystem I Particles. Eur J Biochem 213(3):1133-1138.

Medina M, Gomezmoreno C, Tollin G (1992). Effects of Chemical Modification

     of Anabaena Flavodoxin and Ferredoxin NADP+ Reductase on the Kinetics of

     Interprotein Electron Transfer Reactions. Eur J Biochem 210(2):577-583.

Schmitz O, Kentemich T, Zimmer W, Hundeshagen B, Bothe H (1993).

     Identification of the nifJ Gene Coding for Pyruvate-Ferredoxin

     Oxidoreductase in Dinitrogen-Fixing Cyanobacteria. Arch Microbiol


Stockman BJ, Euvrard A, Kloosterman DA, Scahill TA, Swenson RP (1993). 1H and

     15N Resonance Assignments and Solution Secondary Structure of Oxidized

     Desulfovibrio Vulgaris Flavodoxin Determined by Heteronuclear

     3-Dimensional NMR Spectroscopy. J Biomol Nmr 3(2):133-149.

Tamagnini P, Yakunin AF, Gogotov IN, Lindblad P (1993). Plant-Type and

     Bacterial-Type Ferredoxins in a Nitrogen-Fixing Cyanobacterium - Nostoc

     Sp Strain PCC 73102. FEMS Microbiol Lett 107(1):37-42.

Yakunin AF, Hallenbeck PC, Troshina OY, Gogotov IN (1993). Purification and

     Properties of a Bacterial-Type Ferredoxin from the Nitrogen-Fixing

     Cyanobacterium Anabaena variabilis ATCC 29413. Biochim Biophys Acta


Bakels RHA, Vanwalraven HS, Krab K, Scholts MJC, Kraayenhof R (1993). On the

     Activation Mechanism of the H+-ATP Synthase and Unusual Thermodynamic

     Properties in the Alkalophilic Cyanobacterium Spirulina platensis. Eur J

     Biochem 213(3):957-964.

Krab K, Bakels RHA, Scholts MJC, Vanwalraven HS (1993). Activation of the

     H+-ATP Synthase in Thylakoid Vesicles from the Cyanobacterium

     Synechococcus 6716 by ‏H - Including a Comparison with Chloroplasts, and

     Introducing a New Method to Calibrate Light-Induced. Biochim Biophys Acta


Krenn BE, Koppenaal F, Vanwalraven HS, Krab K, Kraayenhof R (1993).

     Co-reconstitution of the H+-ATP Synthase and Cytochrome b563/c554 Complex

     from a Thermophilic Cyanobacterium - High ATP Yield and Mutual Effects on

     the Enzymatic Activities. Biochim Biophys Acta 1140(3):271-281.

Schluchter WM, Zhao JD, Bryant DA (1993). Isolation and Characterization of

     the ndhF Gene of Synechococcus Sp Strain PCC 7002 and Initial

     Characterization of an Interposon Mutant. J Bacteriol 175(11):3343-3352.


Kuritz T, Ernst A, Black TA, Wolk CP (1993). High-Resolution Mapping of

     Genetic Loci of Anabaena PCC 7120 Required for Photosynthesis and Nitrogen

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Vachhani AK, Iyer RK, Tuli R (1993). A Mobilizable Shuttle Vector for the

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Walton DK, Gendel SM, Atherly AG (1993). DNA Sequence and Shuttle Vector

     Construction of Plasmid pGL3 from Plectonema boryanum PCC 6306. Nucleic

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Kim ST, Sancar A (1993). Photochemistry, Photophysics, and Mechanism of

     Pyrimidine Dimer Repair by DNA Photolyase. Photochem Photobiol


Kovacs SA, Oneil J, Watcharapijarn J, Moekirvan C, Vijay S, Silva V (1993).

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     Cyanobacterium and a Gram-Positive Eubacterium. J Bacteriol


Piechula S, Kur J, Bielawski K, Podhajska AJ (1992). Isolation and

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Lehel C, Los D, Wada H, Gyorgyei J, Horvath I, Kovacs E, Murata N, Vigh L

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Schmidt J, Subramanian AR (1993). Sequence of the Cyanobacterial tRNA(w) Gene

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     the Acceptor Stem. Nucleic Acids Res 21(10):2519.

Nakai M, Sugita D, Omata T, Endo T (1993). SecY Protein Is Localized in Both

     the Cytoplasmic and Thylakoid Membranes in the Cyanobacterium

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                              APPLIED CYANOBACTERIOLOGY

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     Monocrotophos and Quinalphos with Anabaena torulosa Isolated from Rice

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Megharaj M, Pearson HW, Venkateswarlu K (1993). Physiological and

     Morphological Alterations Induced by Carbaryl and 1-Naphthol Combinations

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Milicia F, Favilli F (1993). Azolla symbiotic system's application as

     biofertilizer for green garden crops. Symbiosis 14:495-500.

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Obreht Z, Kerby NW, Gantar M, Rowell P (1993). Effects of root-associated

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Obulakondaiah M, Sreenivasulu C, Venkateswarlu K (1993). Nontarget Effects

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     wetland rice fields. In: Soil Microbial Ecology (FB Metting Jr, ed).

     Marcel Dekker, New York, pp.417-455.

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     Cyanobacteria - Spirulina maxima in Continuous Culture in Response to

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     Cyanobacterium Anabaena Sp PCC 7120 Expressing Gene-51 and Gene-42 of

     Bacillus Sphaericus Sp 2297. FEMS Microbiol Lett 107(2-3):247-250.

Sailer M, Helms GL, Henkel T, Niemczura WP, Stiles ME, Vederas JC (1993).

     15N-Labeled and 13C-Labeled Media from Anabaena Sp for Universal Isotopic

     Labeling of Bacteriocins - NMR Resonance Assignments of Leucocin-A from

     Leuconostoc gelidum and Nisin-A from Lactococcus lactis. Biochemistry




Bianca Brahamsha    Scripps Institute of Oceonagraphy, University of

                    California-San Diego, La Jolla CA 92093 U.S.A.

                    (E-mail) BBrahamsha@Ssurf.Ucsd.Edu

John Cobley         Dept. of Chemistry, University of San Francisco, 2130

                    Fulton St., San Francsico CA 94117 U.S.A.

                    (Tel) 415-666-6450, (E-mail) Cobley@Compserv.Usfca.Edu

Jari Kiviranta      Dept. of Pharmacy, P.O. Box 15, University of Helsinki,

                    FIN-0014 Helsinki, FINLAND. (Tel) 358-0-1912635, 

                    (Fax) 358-0-1912786.

Rogerio Lacaz-Ruiz  Universidade de Sao Paulo - Faculdade de Zootecnia, CP23

                    CEP13630-000 Pirassununga-sp, BRAZIL. 

                    (E-mail) RogLRuiz@Brusp.Ansp.Br

Nick Mann           Dept. of Biological Sciences, University of Warwick,

                    Coventry, CV4 7AL UK (Tel) 0203-523523, (Fax) 0203-523568

                    (E-mail) NM@Dna.Bio.Warwick.Ac.Uk

Martin Mulligan     Dept. of Biochemistry, Memorial Univ. of Newfoundland,

                    St. John's, Newfoundland A1B 3X9 CANADA.

                    (Tel) 709-737-7978, (Fax) 709-737-2422,


Brian Palenik       Marine Biology Research Division, Scripps Institution of

                    Oceanography, University of California-San Diego, La

                    Jolla CA 92093 U.S.A. (E-mail)

Laurie Richardson   Dept. of Biological Sciences, Florida International

                    University, University Park, Miami CA 33199 U.S.A.

                    (Tel) 305-348-1988, (Fax) 305-348-1986,

                    (E-mail) RichardL@Servax.Bitnet

Mike Schaefer       School of Biological Sciences, University of Missouri-KC

                    BSB 213, 5100 Rockhill Rd, Kansas City MO 64110-2499

                    USA (Tel) 816-235-2573, (E-mail) MSchaefer@Vax1.Umkc.Edu

Olav Skulberg       Norwegian Institute for Water Research, 69

                    Korsvall, N-0808 Oslo 8 NORWAY

Bob Tabita          Department of Microbiology, The Ohio State University,

                    484 West 12th Avenue, Columbus OH  43210-1292 U.S.A.

                    (Tel) 614-292-4297, (Fax) 614-292-1538

                    (E-mail) RTabita@Magnus.Acs.Ohio-State.Edu

Nikos Tsinoremas    Dept. of Biology, Texas A&M University, College Station

                    TX 77843 U.S.A. (E-mail) Nicholas@Bio.Tamu.Edu

Bob Webb            Dept. of Biological Sciences, University of Texas at El

                    Paso, El Paso TX U.S.A. (E-mail) jx02@utep.Bitnet

Jindong Zhao        Applied Biosystems, 850 Lincoln Centre Dr., Foster City,

                    CA 94404 U.S.A. (Tel) 415-570-6667


Send CONTRIBUTIONS to one of the addresses listed below.  To SUBSCRIBE, send

$10 U.S. (or equivalent in any currency) per year to Jeff Elhai, along with

your name, telephone, FAX, and EMail numbers (if any), and a brief

description of your research interests for inclusion in the next Directory

of Cyanobacteriologists.  If it is difficult for you to send hard currency,

send a note indicating your interest.

AUSTRALIA     Steve Delaney            Department of Biotechnology,

 /NEW ZEALAND                          University of New South Wales, P.O.

                                       Box 1, Kensington, New South Wales

                                       AUSTRALIA 2033

AUSTRIA       Georg Schmetterer        Institut fur Physikalische Chemie,

                                       Wahringerstrasse 42, A-1090 Wien

                                       (EMail) A8422dad@Awiuni11

CANADA        Neil Strauss             Dept. of Botany, University of

                                       Toronto, Toronto, Ontario  M5S 1A1.

                                       (E-mail) StrausNA@gpu.utcs.UToronto.Ca

P.R.CHINA     Chao-Tsi Tseng           Centre of Marine Sciences, Department 

                                       of Biology, Nanjing University,


CZECHOSLOV.   Jiri Komarek             Institute of Botany, CAS Dept. of

                                       Hydrobotany, Dukelske 145, CS-37982


FRANCE        Nicole Tandeau de Marsac Physiologie Microbienne, Institut

                                       Pasteur, 29 rue du Dr. Roux, 75724

                                       Paris Cedex 15. (EMail) Cyano@Pasteur

GERMANY       Wolfgang Lockau          Institut fuer Botanik, Universitaet,

                                       Universitaetsstr. 31, 8400


INDIA         Joe Thomas               Biotechnology Division, SPIC Science

                                       Foundation, 110 Mount Road, Madras

                                       600 032

ISRAEL        Elisha Tel-Or            Dept. of Agricultural Botany, The

                                       Hebrew University, Rehovot 76100

                                       (Tel) 08-481262

ITALY         Mario Tredici            Centro di Studio dei Microorganismi

                                       Autotrof. (C.N.R.), P.le. delle

                                       Cascine 27 51044 Firenze

                                       (E-mail) D47000@Ifiidg.Fi.Cnr.It

NETHERLANDS   Luuc Mur                 Laboratorium voor Microbiologie,

                                       Universiteit voor Amsterdam, Nieuwe

                                       Achtergracht 127, 1018 WS Amsterdam

SCANDANAVIA   Olav Skulberg            Norwegian Institute for Water

                                       Research, 69 Korsvall, N-0808

                                       Oslo 8 NORWAY

U.K.          Tony Walsby              Dept. of Botany, University of

                                       Bristol, Bristol BS8 1UG

ANYWHERE ELSE Jeff Elhai               Dept. of Biological Sciences, Florida

                                       International University, University

                                       Park Campus, Miami FL 33199 USA. 

                                       (Tel) 305-348-3584, (Fax) 305-348-1986

                                       (E-mail) Cyano@Servax.Bitnet

                                            or  Cyano@Servax.Fiu.Edu