Publications

optimal conditions for genetic transformation of the cyanobacterium anacystis nidulans r2.	under optimal conditions, the cyanobacterium anacystis nidulans r2 was transformed to ampicillin resistance at frequencies of greater than 10(7) transformants per microgram of plasmid (pch1) donor dna. no stringent period of competency was detected, and high frequencies of transformation were achieved with cultures at various growth stages. transformation increased with time after addition of donor dna up to 15 to 18 h. the peak of transformation efficiency (transformants/donor molecule) occurre ...	1984	6425267
instability and variable toxicity of hbp-tx, a toxin in the cyanobacterium microcystis aeruginosa.	it was found that autoxidative degradation is responsible for the inactivation of the unstable microcystis toxin hbp-tx. the purified toxin was similar in its properties to the "fast-death-factor" in microcystis, described as a cyclic peptide in the literature. the apparent presence of an entirely different toxin was simulated by the partially inactivated hbp-tx. a number of associated fluorescent compounds were identified as the non-toxic degradation products of the toxin. as a consequence, as ...	1984	6426092
effect of al3+ on electron transport catalysed by photosystem i & ii of photosynthesis in cyanobacterium synechococcus spheroplasts & beet-spinach chloroplasts.		1983	6427098
length of foreign dna in chimeric plasmids determines the efficiency of its integration into the chromosome of the cyanobacterium synechococcus r2.	the photosynthetic cyanobacterium synechococcus r2 is efficiently transformed by dna molecules that contain antibiotic genes from escherichia coli linked to a segment of synechococcus r2 chromosomal dna. antibiotic-resistant transformants result from integration of donor dna into the cyanobacterial chromosome by homologous recombination. foreign dna interrupting the cyanobacterial sequence in the donor molecule integrates by replacement of homologous recipient dna with donor dna containing the f ...	1984	6428977
na+ requirement for growth, photosynthesis, and ph regulation in the alkalotolerant cyanobacterium synechococcus leopoliensis.	we have found that na+ is required for the alkalotolerance of the cyanobacterium synechococcus leopoliensis. cell division did not occur at any ph in the absence of na+, but cells inoculated into na+-free growth medium at ph 6.8 did continue metabolic activity, and over a period of 48 h, the cells became twice their normal size. many of these cells remained viable for at least 59 h and formed colonies on na+ -containing medium. cells grown in the presence of na+ and inoculated into na+ -free gro ...	1984	6429118
effects of pesticides on cyanobacterium plectonema boryanum and cyanophage lpp-1.	cyanobacterium plectonema boryanum iu 594 and cyanophage lpp-1 were used as indicator organisms in a bioassay of 16 pesticides. experiments such as spot tests, disk assays, growth curves, and one-step growth experiments were used to examine the effects of pesticides on the host and virus. also, experiments were done in which host or virus was incubated in pesticide solutions and then assayed for pfu. p. boryanum was inhibited by four herbicides: 3-(3,4-dichlorophenyl)-1,1-dimethylurea (dcmu), 1, ...	1984	6430230
na+/h+ exchange in the cyanobacterium synechococcus 6311.	the cyanobacterium synechococcus 6311 adapts to grow in 0.6 m nacl by developing an efficient system for sodium extrusion. in the present investigation cells loaded with nac1 were subjected to a large dilution. changes in fluorescence quenching of acridine orange as a function of transmembrane na+ gradients provide evidence that na+/h+ exchange activity greatly enhanced in salt-adapted cells.	1984	6430295
vanadate and dicyclohexylcarbodiimide insensitive proton extrusion from oxygen pulsed cells of the cyanobacterium anacystis nidulans.	oxygen pulses applied to dark anaerobic suspensions of anacystis nidulans provoked immediate acidification of the external medium. the reaction was inhibited only 75% by dicyclohexylcarbodiimide and 7-chloro-4-nitrobenz-2-oxa-1,3-diazole at concentrations which completely arrested all oxidative phosphorylation. carbonyl cyanide m-chlorophenylhydrazone eliminated the acidification of oxygen pulsed cell suspensions while ortho-vanadate and diethylstilbestrol had no effect. no lag occurred between ...	1984	6433918
catalytically active hybrids formed in vitro between large and small subunits of different procaryotic ribulose bisphosphate carboxylases.	ribulose bisphosphate carboxylase from the procaryotic green alga, prochloron (the symbiont of lissoclinum patellum), has eight large and eight small subunits, and a low affinity for co2, similar to that of cyanobacterial carboxylases. the small subunits were progressively removed from this carboxylase and from that from the cyanobacterium, synechococcus acmm 323, by twice-repeated, mild-acid precipitation. this procedure produced large-subunit octamers, greatly depleted in small subunits, as we ...	1984	6435536
regulation of the nitrate reductase level in anacystis nidulans: activity decay under nitrogen stress.	the in vivo stability of ferredoxin-nitrate reductase from the cyanobacterium anacystis nidulans under conditions of inhibited protein synthesis has been studied in nitrate-grown cells. a light-promoted rapid decay in cellular nitrate reductase activity took place in the absence of any added nitrogen source, but not in the presence of nitrate, nitrite, or ammonium. the inactivation process seemed to proceed in two sequential steps. the first step required both light and oxygen, and was inhibited ...	1984	6437330
cloning and sequencing of the genes encoding the alpha and beta subunits of c-phycocyanin from the cyanobacterium agmenellum quadruplicatum.	synthetic oligonucleotide probes were used to identify a cloned dna fragment from the cyanobacterium agmenellum quadruplicatum that contains the genes for the alpha and beta subunits of c-phycocyanin. the coding region for the alpha-subunit gene begins 108 base pairs downstream from the 3' end of the beta-subunit structural gene. the sequences of the coding regions for both genes have been determined as well as 379 base pairs of 5' flanking region, 204 base pairs of 3' flanking region, and the 1 ...	1984	6438628
phylogeny of the 5s ribosomal rna from synechococcus lividus ii: the cyanobacterial/chloroplast 5s rnas form a common structural class.	the complete nucleotide sequence of the 5s ribosomal rna from the cyanobacterium synechococcus lividus ii has been determined. the sequence is (sequence in text) this 5s rna has the cyanobacterial- and chloroplast-specific nucleotide insertion between positions 30 and 31 (using the numbering system of the generalized eubacterial 5s rna) and the chloroplast-specific nucleotide-deletion signature between positions 34 and 39. the 5s rna of s. lividus ii has 27 base differences compared with the 5s ...	1984	6443313
influence of growth temperature on structure, thermostability and kinetic properties of the atpase coupling factor af1 of a thermophilic blue-green alga (cyanobacterium).	the coupling factor af1 isolated from cells of the thermophilic blue-green alga mastigocladus laminosus grown at 40 degrees c, 50 degrees c and 60 degrees c is investigated and compared with the chloroplast coupling factor cf1. it is demonstrated that the structure of af1 is affected by the growth temperature. the af1 from 60 degrees c shows a split alpha-band in dodecylsulfate/polyacrylamide gel electrophoresis which is not observed in af1 from 40 degrees c or from 50 degrees c. only the af1 fr ...	1981	6456904
validity of the tritiated thymidine method for estimating bacterial growth rates: measurement of isotope dilution during dna synthesis.	the rate of tritiated thymidine incorporation into dna was used to estimate bacterial growth rates in aquatic environments. to be accurate, the calculation of growth rates has to include a factor for the dilution of isotope before incorporation. the validity of an isotope dilution analysis to determine this factor was verified in experiments reported here with cultures of a marine bacterium growing in a chemostat. growth rates calculated from data on chemostat dilution rates and cell density agr ...	1984	6517579
species variation in kinetic properties of ribulose 1,5-bisphosphate carboxylase/oxygenase.	several kinetic parameters of ribulose-1,5-bisphosphate (rubp) carboxylase/oxygenase from different species were measured and compared. the co2/o2 specificity (vcko/vokc) was found to be about 80 in the enzymes from several c3 species and two c4 species. specificity values of 58 and 70, respectively, were found in enzymes from the c4 plants setaria italica and sorghum bicolor. two enzymes from cyanobacteria had values of about 50. substitution of mn2+ for mg2+ reduced the co2/o2 specificity by a ...	1983	6582802
cyanophycin granule polypeptide formation and degradation in the cyanobacterium aphanocapsa 6308.	the effect of a number of conditions on the amount of cyanophycin granule polypeptide [multi-l-arginyl poly(l-aspartic acid)] formed in the unicellular cyanobacterium aphanocapsa 6308 was determined. light, co2, sulfur, and phosphorus starvation as well as the addition of arginine to culture media increased the amount of cyanophycin granule polypeptide in cells when compared with that in cells grown under conditions optimal for growth. nitrogen limitation and reduction of growth temperature to 3 ...	1980	6767688
structure and composition of cyanophycin granules in the cyanobacterium aphanocapsa 6308.	cyanophycin granules in the unicellular cyanobacterium aphanocapsa 6308 were examined with the electron microscope in both thin section and by freeze-fracture techniques. purified granules were examined with the electron microscope, by arginine determinations, by chromatography, and by elemental analysis. they are similar in ultrastructure and composition to those isolated from the nitrogen-fixing cyanobacterium anabaena cylindrica, consisting of equal molar quantities of l-arginine and l-aspart ...	1980	6767696
regulatory effect of hydrogen on nitrogenase activity of the blue-green alga (cyanobacterium) nostoc muscorum.	preincubation of the blue-green alga (cyanobacterium) nostoc muscorum under an atmosphere of argon plus acetylene in the light led to a greater than fourfold increase of light-induced hydrogen evolution and to a 50% increase of acetylene reduction, as compared to cells that had not been preconditioned. the basic and the increased hydrogen evolution were both due to nitrogenase activity. furthermore, after preincubation the hydrogen uptake, usually observed with unconditional cells, was abolished ...	1980	6767700
control of phycobiliprotein proteolysis and heterocyst differentiation in anabaena.	phycobiliprotein degradation can be initiated in cultures of the cyanobacterium anabaena by removal of combined nitrogen from the medium. certain strains of anabaena differentiate cells specialized for aerobic nitrogen fixation (heterocysts) under such conditions. we describe here a procedure for the preparation of extracts from heterocysts or vegetative cells that contain an activity capable of degrading only the phycobiliproteins in a mixture of soluble anabaena proteins in vitro. this activit ...	1980	6767709
wavelength modulation of phycoerythrin synthesis in synechocystis sp. 6701.	the spectral dependence of phycoerythrin synthesis has been studied in a unicellular photautotrophic cyanobacterium, synechocystis sp. 6701, in which phycoerythrin synthesis alone is under chromatic control. cells were partially depleted of their phycobiliprotein pigments through nitrate starvation in the light. addition of nitrate to the culture medium allowed synthesis of phycobiliproteins in the dark. this synthesis occurred at the expense of the glycogen reserve accumulated during the period ...	1980	6768711
cytochrome f from spinach and cyanobacteria. purification and characterization.	cytochrome f has been purified from spinach chloroplasts and from the photosynthetic membranes of the cyanobacterium spirulina maxima. the spinach protein has an isoelectric point of 5.2 and gives a single band on isoelectric focusing gels. the s. maxima cytochrome shows a major band with a pi of 4.01 and a minor band with a pi of 3.97. s. maxima cytochrome f has a molecular weight approximately 38,000 and is monomeric, while the spinach protein is slightly smaller, approximately 36,000 daltons, ...	1980	6768742
growth of legionella pneumophila in association with blue-green algae (cyanobacteria).	legionella pneumophila (legionnaires disease bacterium) of serogroup 1 was isolated from an algal-bacterial mat community growing at 45 degrees c in a man-made thermal effluent. this isolate was grown in mineral salts medium at 45 degrees c in association with the blue-green alga (cyanobacterium) fischerella sp. over a ph range of 6.9 to 7.6. l. pneumophila was apparently using algal extracellular products as its carbon and energy sources. these observations indicate that the temperature, ph, an ...	1980	6769388
oxidation of biphenyl by the cyanobacterium, oscillatoria sp., strain jcm.	the oxidation of biphenyl by cyanobacterium, oscillatoria sp., strain jcm was studied. the organism grown photoautotrophically in the presence of biphenyl oxidized biphenyl to form 4-hydroxybiphenyl. the structure of the metabolite was elucidated by ultraviolet and mass spectra and shown to be identical to authentic 4-hydroxybiphenyl. in addition this metabolite had properties identical to 4-hydroxybiphenyl when analyzed by thin-layer and high-pressure liquid chromatography. experiments with [14 ...	1980	6769418
tungsten-induced inactivation of molybdoenzymes in anabaena.	the effect of tungsten on growth and activity of two molybdoenzymes has been studied in a nitrogen-fixing heterocystous cyanobacterium, anabaena. sodium tungstate inhibited growth and inactivated nitrogenase and nitrate reductase. the activity of both enzymes was restored by the addition of molybdenum. tungstate treatment caused increase in heterocyst frequency both in no3- medium and in medium free of combined nitrogen. these results suggest that tungstate treatment inactivates the molybdoenzym ...	1980	6769488
cyanobacterial phycobilisomes. particles from synechocystis 6701 and two pigment mutants.	the phycobilisomes of the unicellular cyanobacterium synechocystis 6701, grown in white light, contain c-phycoerythrin, c-phycocyanin, and allophycocyanin in a molar ration of approximately 2:2:1, and in addition, polypeptides of 99, 46, 33.5, 31.5, 30.5, and 27 x 10(3) daltons, as well as a trace of a approximately 9 x 10(3)-dalton component. two nitrosoguanidine-induced mutants of this organism produce aberrant phycobilisomes. crude cell extracts of these mutants, 6701-ntg25 and ntg31, contain ...	1980	6771296
ultrastructure of the cell wall of a synechocystis strain.	the ultrastructure of the cell wall of a synechocystis strain, isolated from the gulf of finland, was studied using several electron microscopic techniques. this cyanobacterium has numerous projections which were observed to penetrate the cell wall complex. an additional layer (al) was associated with the outer membrane. an additional external wall layer (el) was connected to the outer membrane complex by thin fibers as revealed by ruthenium red staining. a hexagonal arrangement of the subunits ...	1980	6773644
active transport and accumulation of bicarbonate by a unicellular cyanobacterium.	the rates of inorganic carbon accumulation and carbon fixation in light by the unicellular cyanobacterim coccohloris peniocystis have been determined. cells incubated in the light in medium containing h14co3- were rapidly separated from the medium by centrifugation through silicone oil into a strongly basic terminating solution. samples of these inactivated cells were assayed to determine total 14c accumulation, and acid-treated samples were assayed to determine 14c fixation. the rate of transpo ...	1980	6773925
[cell cycle characteristics of chamaesiphon confervicola, a cyanobacterium forming exospores].	a strain of the cyanobacterium chamaesiphon confervicola was isolated and studied. the strain multiplies by means of exospores, round cells which separate from the parent cell and attach to the substrate with a short pedicle and a mucous pad. the exospore transforms into a cylindrical cell surrounded with a sheath in the process of growth. new exospores separate from the pole of the cell opposite to the pedicle through a rupture in the sheath. either one exospore or numerous exospores formed as ...	1980	6774216
molecular architecture of a light-harvesting antenna. comparison of wild type and mutant synechococcus 6301 phycobilisomes.	phycobilisomes of the cyanobacterium synechococcus 6301 contain c-phycocyanin and allophycocyanin in a molar ratio of approximately 3.8:1, a minor biliprotein, allophycocyanin b, and nonpigmented polypeptides of 75, 33, 30, and 27 kilodaltons. a nitrosoguanidine-induced mutant an112 produces altered phycobilisomes with the molar ratio of c-phycocyanin to allophycocyanin reduced to approximately 1.4:1 and without any of the 33- and 30-kilodalton polypeptides. the mutant and wild type phycobilisom ...	1980	6776125
ecophysiological studies on spirulina platensis. effect of temperature, light intensity and nitrate concentration on growth and ultrastructure.	the ultrastructure of the cyanobacterium spirulina platensis was studied in relation to temperature, light intensity and nitrate concentration. the organism was able to grow in media supplied with nitrate in concentrations up to 250 mm. high nitrate concentrations increased the yield and growth rate at temperatures above 35 degeees c. occurrence, distribution and abundance of cyanophycin granules, polyglucan granules, cylindrical bodies, carboxysomes and mesosomes varied widely in relation to th ...	1980	6776891
increase of nitrogenase activity in the blue-green alga nostoc muscorum (cyanobacterium).	preincubation of the blue-green alga (cyanobacterium) nostoc muscorum under hydrogen or argon (nongrowing conditions, neither co(2) nor n(2) or bound nitrogen present) in the light resulted in a two- to fourfold increase of light-induced hydrogen evolution and a 30% increase of acetylene reduction. preincubation under the same gases in the dark led to a decrease of both activities. cultivation of algae under a hydrogen-containing atmosphere (n(2), h(2), co(2)) increased neither hydrogen nor ethy ...	1980	6777364
bacteriophage infection interferes with guanosine 3'-diphosphate-5'-diphosphate accumulation induced by energy and nitrogen starvation in the cyanobacterium anacystis nidulans.	anacystis nidulans accumulates large amounts of guanosine 3'-diphosphate-5'-diphosphate (ppgpp) upon nutritional or energy starvation induced by light-to-dark shift, treatment with carbonylcyanide-m-chlorophenylhydrazone (an uncoupler), or treatment with l-methionine-dl-sulfoximine (an inducer of nitrogen starvation). in contrast to healthy a. nidulans cells, those infected by as-1 cyanophage do not respond with ppgpp accumulation when starved after about one-third of the complete infection cyc ...	1980	6777368
[reactions of cyanobacteria to certain heavy metals].	the effect of zinc and cobalt chlorides on cellular growth, n2 fixation, photosynthesis and changes in the content of na+ and k+ ions in cells was studied with the blue-green alga (cyanobacterium) anabaena spheroides. the cells were most susceptible to the action of cobalt ions at the beginning of the logarithmic growth phase, and least sensitive by the end of the phase. cobalt ions were more toxic than zinc ions. the salts of heavy metals inhibited active transport of ions into the algal cells.	1980	6777649
molecular architecture of a light-harvesting antenna. in vitro assembly of the rod substructures of synechococcus 6301 phycobilisomes.	the 75-, 33-, 30-, and 27-kilodalton polypeptide components ("linker polypeptides") of the phycobilisome of the unicellular cyanobacterium synechococcus 6301 have been purified and characterized. in 0.6 m nak phosphate buffer at ph 8, the 33-, 30-, and 27-kilodalton polypeptides assemble phycocyanin into ordered aggregates, whereas the 75-kilodalton polypeptide does not interact with phycocyanin. in the presence of the 33- and 30-kilodalton polypeptides, phycocyanin is assembled into hexameric d ...	1981	6782105
structural characterization of the cyanophycin granule polypeptide of anabaena cylindrica by circular dichroism and raman spectroscopy.	the cyanophycin granule polypeptide, or multi-l-arginyl-poly(l-aspartic acid), from the filamentous cyanobacterium anabaena cylindrica has been examined by circular dichroism and laser raman spectroscopy. the polypeptide exhibits defined secondary structure in acidic solution, but not in alkaline medium. raman spectra show the structure of the insoluble (storage?) form of the polypeptide is similar but not identical to that of the acid soluble form. analysis of the cd spectra suggests that beta- ...	1980	6783080
internal and external membrane proteins of the cyanobacterium, synechococcus cedrorum.	the protein composition and architecture of the photosynthetic membranes from the cyanobacterium, synechococcus cedrorum, were analyzed with the aid of site-specific labels. using membranes labeled with 35s, about 50 membrane proteins can be detected by sodium dodecyl sulfate acrylamide gel electrophoresis. approximately half of the proteins are accessible to modification by the impermeant probe, lactoperoxidase, indicating that they have surface-exposed domains. at least six of these external p ...	1981	6783086
molecular heterogeneity of ferredoxin:nadp+ oxidoreductase from the cyanobacterium anabaena cylindrica.	the enzyme ferredoxin:nadp+ oxidoreductase (ec 1.18.1.2) from whole filaments of anabaena cylindrica can be separated into four major fractions by chromatography on phosphocellulose; chromatography using ferredoxin-sepharose 4b proved to be less satisfactory in separating the fractions. the purified fractions, designated 1, 2, 3 and 4, all showed diaphorase and ferredoxin-dependent cytochrome c reductase activity. the major fractions present were 2 and 3 which were each obtained in an electropho ...	1981	6783100
strategies of response to copper, cadmium, and lead by a blue-green and a green alga.	the toxic metal ions cu2+, cd2+, and pb2+ inhibited growth of the green alga ankistrodesmus braunii and the blue-green alga (cyanobacterium) anabaena, strain 7120. some concentrations of cu lysed anabaena 7120 at early, but not late, stages of growth. the other metals inhibited growth without causing lysis. adding the chelating agent nitrilotriacetic acid (nta) did not reduce, and in some cases increased, metal toxicity to anabaena 7120. this suggests that these metals do not act on this alga on ...	1980	6783279
occurrence and localization of two distinct hydrogenases in the heterocystous cyanobacterium anabaena sp. strain 7120.	two distinct types of hydrogenase occur in anabaena 7120 and are distinguishable in whole filaments by the application of selective assay methods. a reversible hydrogenase occurs both in heterocysts and vegetative cells and can be selectively assayed by measuring h2 evolution from reduced methyl viologen. activities in aerobically grown filaments were low but could be increased by 2 to 3 orders of magnitude by growing cells microaerobically. the presence of the reversible hydrogenase was indepen ...	1981	6783614
metronidazole and the isolation of temperature-sensitive photosynthetic mutants in cyanobacteria.	a procedure has been developed for use of metronidazole (2-methyl-5-nitroimidazole-1-ethanol) as an enrichment agent during the isolation of temperature-sensitive, photosynthetic mutants in the cyanobacterium synechococcus cedrorum. the protocol includes incubation with this drug following mutagenesis with n-methyl-n'-nitro-n-nitrosoguanidine. incubation of photosynthetically active s. cedrorum cells with 1 mm metronidazole causes a light-dependent reduction of cell viability. maximum reduction ...	1980	6783642
oscillations of the nad(p)h pool size and of the redox state of a cytochrome b during dark respiration of the blue-green alga, anacystis nidulans.	oscillations of the oxygen uptake rate of the blue-green alga (cyanobacterium) anacystis nidulans were induced by light pulses. the pool size of nad(p)h and the redox state of a cytochrome b showed oscillations of similar shape and frequency. phase diagrams revealed that these three oscillations were presumably linked. the cytochrome b should be a part of the respiratory chain of this blue-green alga. the oscillations were inducible only in a limited physiological state of the alga.	1980	6786340
fine structure of the cell wall of the cyanobacterium microcoleus vaginatus (vauch.) gomont.	the organization of the cell wall of microcoleus vaginatus (vauch.) gomont is described. the four layered wall possesses an unusual layer 2 (mucopolymer containing layer). this layer is 20 nm thick near the crosswall, but abruptly increases in thickness to 90 nm away from the crosswall. in many filaments a perforated sheet 20 nm in thickness was observed on the face of layer 2 which is toward the plasma membrane. it is suggested that this sheet represents an area of mobilization of mucopolymer f ...	1981	6786835
nitrogenase activity and membrane electrogenesis in the cyanobacterium anabaena variabilis kütz.	relationships between nitrogenase activity and individual components of the proton electrochemical potential gradient (delta microh+) in anabaena variabilis have been investigated. the ionophore nigericin was found to collapse delta ph in favour of the membrane potential (delta psi); hyperpolarization of delta psi was correlated with an increase in nitrogenase activity. a positive relationship between nitrogenase activity and membrane potential was also observed using the ionophore valinomycin a ...	1981	6786885
metabolism of sulfur compounds by whole filaments and heterocysts of anabaena variabilis.	filaments of the heterocyst-forming cyanobacterium anabaena variabilis reproduced 35so4(2)-, incorporating 35s into cysteine, methionine, glutathione, sulfolipid, and several unidentified metabolites. the majority of the incorporated label accumulated in reduced glutathione. heterocysts isolated from labeled filaments contained the same major labeled products. isolated, metabolically active heterocysts were unable to reduce 35so4(2)-, but were able to incorporate 35s2- into cysteine and glutathi ...	1981	6787010
characterization of the transport of potassium ions in the cyanobacterium anabaena variabilis kütz.	interrelationships between potassium-ion transport and transplasmalemma electrical-potential difference (delta psi m) have been investigated in anabaena variabilis (atcc 29413) by measuring k+ translocation and membrane potential in parallel. at ph 7.0, 5 mmol . dm-3 external k+, there was a thirtyfold accumulation of k+. the k+ equilibrium potential was lower (more negative) than the measured membrane potential by up to 20 mv, (delta psi k+ = -90 mv; delta psi m = -70 mv to -75 mv, respectively ...	1981	6788551
isolation and characterization of thioredoxin from the cyanobacterium, anabaena sp.	thioredoxin from anabaena sp. has been purified 800-fold with an assay based on the reduction of insulin disulfides by nadph and the heterologous calf thymus thioredoxin reductase. the final material was homogeneous on polyacrylamide gel electrophoresis and had a molecular weight of 12,000; the nh2-terminal residue was serine and the cooh-terminal was leucine. anabaena thioredoxin-(sh)2 is a hydrogen donor for the adenosylcobalamin-dependent anabaena ribonucleotide reductase and is equally activ ...	1981	6790538
kinetics and subunit interactions of ribulose bisphosphate carboxylase-oxygenase from the cyanobacterium, synechococcus sp.		1981	6790541
the complete amino acid sequence of both subunits of allophycocyanin, a light harvesting protein-pigment complex from the cyanobacterium mastigocladus laminosus.	the amino acid sequences of the alpha- and beta-subunit of allophycocyanin, a water-soluble light-harvesting protein-pigment complex from the thermophilic cyanobacterium mastigocladus laminosus have been determined. the alpha-chain consists of 160 amino acid residues and the beta-chain of 161 amino acid residues. the homology of the alpha- and beta-chains is 37%. a comparison with c-phycocyanin reveals that the second chromophore of the c-phycocyanin beta-subunit is attached to an inserted pepti ...	1981	6792029
production of amino acids by analog-resistant mutants of the cyanobacterium spirulina platensis.	mutants of spirulina platensis resistant to 5-fluorotryptophan, beta-3-thienyl-alanine, ethionine, p-fluorophenylalanine, or azetidine-2-carboxylic acid were isolated. some of these mutants appeared to be resistant to more than one analog and to overproduce the corresponding amino acids. a second group was composed of mutants that were resistant to one analog only. of the latter mutants, one resistant to azetidine-2-carboxylic acid was found to overproduce proline only, whereas one resistant to ...	1981	6792182
accumulation of guanosine tetraphosphate (ppgpp) under nitrogen starvation in anacystis nidulans, a cyanobacterium.	the effect of nitrate deprivation on cell growth and nucleotide level was studied in anacystis nidulans. a 10-fold reduction in nitrate level resulted in a drastic slowdown of growth. upon addition of nitrate to the starving cultures, after a lag period, the cells resumed growth. nutritional shift-down induced a transitory expansion of the guanosine tetraphosphate (ppgpp) pool, preceded by a transitory increase in gtp and atp concentrations. after having reached peak values, the concentration of ...	1981	6793016
gliding motility in aphanothece halophytica: analysis of wall proteins in mot mutants.	the unicellular cyanobacterium aphanothece halophytica (pcc 7418) is motile, and spontaneous nonmotile (mot) mutants accumulate when the organism is subcultured. analysis of mot mutants suggests that a glycoprotein in the cell wall is involved in the motility mechanism. proteins from the wall fraction of the wild type and five mot clones were analyzed by gradient sodium dodecyl sulfate-acrylamide gel electrophoresis. four clones were similar to the wild type, and one clone, mot-3, was missing a ...	1981	6793555
phosphorus-31 nuclear magnetic resonance analysis of internal ph during photosynthesis in the cyanobacterium synechococcus.	phosphorus-31 nuclear magnetic resonance (31p nmr) spectra were obtained from actively photosynthesizing and darkened suspensions of the unicellular cyanobacterium synechococcus. these spectra show intracellular resonances belonging to inorganic phosphate (pi), a sugar phosphate (sugar-p), nucleotide di- and triphosphates, and poly-phosphates. the ph-dependent chemical shifts of pi and sugar-p allowed the estimation of intracellular ph. when irradiated with high-intensity tungsten-halogen light ...	1981	6794618
hydrogen uptake by the nitrogen-starved cyanobacterium anabaena cylindrica.		1981	6795997
3'-terminal conserved loops of 16s rrnas from the cyanobacterium synechococcus an pcc 6301 and maize chloroplast differ only in two bases.		1981	6796078
effects of chromatic illumination on cyanobacterial phycobilisomes. evidence for the specific induction of a second pair of phycocyanin subunits in pseudanabaena 7409 grown in red light.	pseudanabaena 7409 is a chromatically cyanobacterium which photocontrols the synthesis of both phycoerythrin and phycocyanin [tandeau de marsac (1977) j. bacteriol. 130, 82--91]. phycobilisomes, isolated from cells grown in either green or red light, have been dissociated and the component biliproteins purified and characterized. phycobilisomes isolated from cells grown in green light were composed of allophycocyanin b, allophycocyanin, two phycocyanin subunits (one alpha-type and one beta-type ...	1981	6796413
heterocyst differentiation and cell division in the cyanobacterium anabaena cylindrica: effect of high light intensity.	heterocyst differentiation in the cyanobacterium anabaena cylindrica is initiated by the removal of fixed nitrogen from the medium. these specialized cells occur singly at regular intervals within filaments of vegetative cells. incubation of cultures for periods of up to 12 h immediately prior to or following removal of fixed nitrogen, at a light intensity (500 mi einsteins cm-2 s-1) approximately 10-fold higher than that required for optimum growth, resulted in the differentiation of pairs of a ...	1981	6796596
a requirement for edta in the separation of photosystems 1 and 2 from the cyanobacterium chlorogloea fritschii.	fractions enriched in photosystem 1 or photosystem 2 activity have been isolated from the cyanobacterium chlorogloea fritschii after extraction of the membranes with digitonin and triton x-100. separation of the extract into the two components was achieved by using a sepharose 6b column, calibration of which gave kd values of 0.3 for the photosystem 1 fraction and 0.53 for photosystem 2. these values corresponded to molecular weights of approx. 500000 and 90000 respectively. the photosystem 1 pa ...	1981	6797405
internal ph and atp-adp pools in the cyanobacterium synechococcus sp. during exposure to growth-inhibiting low ph.	y-7c-s synechococcus thermophilic strain grew at its maximum rate at ph 8 and above. the growth rate of this strain was inhibited at ph 7.0 and below, and at ph 6.0 there was no sustained growth. at a suboptimal ph, high light intensity further depressed the growth rate. the inhibition of growth resulted neither from pheophytinization nor from a low chlorophyll content. at ph 5.0 a loss of viability preceded the appearance of pheophytin. cells exposed to low, growth-inhibiting external ph levels ...	1982	6798019
rapid transient growth at low ph in the cyanobacterium synechococcus sp.	the thermophilic cyanobacterium synechococcus sp. strain y-7c-s grows at its maximum rate at a high ph (ph 8 and above) the does not show sustained growth below ph 6.5. however, rapidly growing, exponential-phase cells from high-ph cultures continued to grow rapidly for several hours after transfer to ph 6.0 or 5.0. this transient growth represented increases in mass and protein, but cells failed to complete division. viability loss commenced well before the cessation of growth, and cells at ph ...	1982	6798020
accumulation of poly-beta-hydroxybutyrate in spirulina platensis.	poly-beta-hydroxybutyrate has been identified in the cyanobacterium spirulina platensis. the addition of reduced carbon compounds to the growth medium was not required for poly-beta-hydroxybutyrate accumulation. poly-beta-hydroxybutyrate accumulated during exponential growth to 6% of the total dry weight and then decreased during the stationary phase.	1982	6798024
isolation and preliminary characterization of mutants of the cyanobacterium nostoc muscorum resistant to growth inhibition by methylamine.	the wild-type heterocystous and nitrogen-fixing (het+nif+) n. muscorum and its non-heterocystous non-nitrogen-fixing (het-nif-) mutant strain both fail to grow in different inorganic nitrogen media containing 1 mm methylamine hydrochloride (ma). mutants of the het+nif+ and het-nif- parents resistant to growth inhibition by 5 mm ma and thus designated as mar strains were isolated with a frequency of 2.5(+/- 2.4) x 10(6). a mar strain of the het+nif+ and a mar strain of the het-nif- parent were ch ...	1981	6799749
isolation of chlorine-containing antibiotic from the freshwater cyanobacterium scytonema hofmanni.	scytonema hofmanni, a filamentous freshwater cyanobacterium (blue-green alga), produces secondary metabolites which inhibit the growth of other cyanobacteria and green algae. a rapid, qualitative assay for this inhibition has been developed with synechococcus as the test organism. this assay procedure has led to the isolation and characterization of an antibiotic (named cyanobacterin) from scytonema. the antibiotic has a molecular weight of 430 and an empirical formula of c23h23o6cl and contains ...	1982	6800032
biotransformation and toxicity of aniline and aniline derivatives of cyanobacteria.	agmenellum quadruplicatum strain pr-6 and oscillatoria sp. strain jcm grown photoautotrophically in the presence of aniline metabolized the aromatic amine to formanilide, acetanilide and p-aminophenol. the metabolites were isolated by either thin-layer, gas-liquid or high pressure liquid chromatography and identified by comparison of their chromatographic, ultraviolet absorbance and mass spectral properties with those of authentic compounds. the toxicity of aniline derivatives towards agmenellum ...	1981	6800332
photoreactivation and excision repair of uv induced pyrimidine dimers in the unicellular cyanobacterium gloeocapsa alpicola (synechocystis pcc 6308).		1982	6801706
amino acid uptake and energy coupling dependent on photosynthesis in anacystis nidulans.	the photoautotrophic cyanobacterium anacystis nidulans was used to investigate the membrane transport of branched-chain, neutral amino acids and its dependence on photosynthetic reactions. the uptake of alpha-amino [1-14c]isobutyric acid and l-[1-14c]leucine followed michaelis, menten kinetics and resulted in an energy-dependent accumulation. as in bacteria, different uptake systems for neutral amino acids were present: two dag (d-alanine, aminoisobutyric acid, and glycine) systems responsible f ...	1982	6806240
active transport of ferric schizokinen in anabaena sp.	the cyanobacterium anabaena sp. strain atcc 27898 was found to utilize the siderophore schizokinen to accumulate iron from the environment. this organism had previously been shown to produce schizokinen under low-iron conditions, and we observed that the iron-transport capability is also increased in response to iron limitation. uptake activity was specific for ferric schizokinen displayed kinetics typical of a protein-mediated process with an apparent km of 0.04 microm and saturation at high co ...	1982	6806241
occurrence of alpha-tocopherolquinone and alpha-tocopherolquinol in microorganisms.	both alpha-tocopherolquinol and alpha-tocopherolquinone were found in 56 of 93 strains of microorganisms examined. organisms that contained these compounds included the single example of a eucaryotic alga, a euglena, and a cyanobacterium (blue-green alga), 22 of 32 genera of bacteria, and 9 genera of yeasts. in the bacteria and yeasts the levels of quinone and hydroquinone were nearly equal and averaged about 3 nmol of each compound g-1 of packed cells. included among the bacteria that contained ...	1982	6809730
the pyruvate: ferredoxin oxidoreductase in heterocysts of the cyanobacterium anabaena cylindrica.	heterocyst preparations have been obtained which actively perform nitrogen fixation (c2h2 reduction) and contain the enzymes of glycolysis and some of the tricarboxylic acid cycle. pyruvate: ferredoxin oxidoreductase has been unambiguously demonstrated in extracts from heterocysts by the formation of acetylcoenzyme a, co2 and reduced methyl viologen (ferredoxin) from pyruvate, coenzyme a and oxidized methyl viologen (ferredoxin) as well as by the synthesis of pyruvate from co2, acetylcoenzyme a ...	1982	6810949
nitrogenase activity and membrane electrogenesis in the cyanobacterium plectonema boryanum.	the relationships between nitrogenase activity (acetylene reduction) and the transplasmalemma proton electrochemical potential gradient (delta muh+) have been investigated using the non-heterocystous filamentous cyanobacterium plectonema boryanum. by selectively modifying the chemical (delta ph) and electrical (delta psi) components of delta muh+ under conditions in which the size of the atp pool remained unaffected, nitrogenase activity was found to be dependent on, or regulated by delta psi. w ...	1982	6814911
evidence for the presence of highly phosphorylated nucleotides in the cyanobacterium tolypothrix sp.		1982	6816633
multiple forms of chlorophyll-protein complexes from a thermophilic cyanobacterium synechococcus sp.		1982	6817716
structural features unique to the 5 s ribosomal rnas of the thermophilic cyanobacterium synechococcus lividus ii and the green plant chloroplasts.		1982	6820072
efficiency of ferredoxins and flavodoxins as mediators in systems for hydrogen evolution.	1. the efficiencies of ferredoxins and flavodoxins from a range of sources as mediators in systems for hydrogen evolution were assessed. 2. in supporting electron transfer from dithionite to hydrogenase of the bacterium clostridium pasteurianum, highest activity was shown by the ferredoxin from the cyanobacterium chlorogloeopsis fritschii and flavodoxin from the bacterium megasphaera elsdenii. the latter was some twenty times as active as comparable concentrations of methyl viologen. ferredoxins ...	1980	7016115
characterization of a nitrogen-fixation (nif) gene cluster from anabaena azollae 1a shows that closely related cyanobacteria have highly variable but structured intergenic regions.	the exact identity of cyanobacteria that have been cultured from symbiotic associations with the water fern azolla spp., whether they are required in the symbiotic process, and their relationship to the symbiotic species, is a matter of some debate. we have characterized a 6 kb region containing the nifb operon and the nifh gene from cyanobacterium anabaena azollae 1a, a putative symbiont of azolla caroliniana. five complete open reading frames have been sequenced. all are very highly conserved ...	1995	7496536
alterations in protein synthesis in the cyanobacterium synechococcus sp. strain pcc 6301 in response to calendula micrantha extract with molluscicidal activity.	the response to the extract of the egyptian wild herb calendula micrantha, with molluscicidal activity, was examined in the unicellular cyanobacterium synechococcus sp. strain pcc 6301. growth and chlorophyll a of the cells were only slightly affected by low concentrations but drastically reduced by high concentrations. the rate of protein synthesis progressively decreased by increasing extract concentration. the cells preferentially induced the synthesis of a limited number of polypeptides in r ...	1995	7498056
transient accumulation of heme o (cytochrome o) in the cytoplasmic membrane of semi-anaerobic anacystis nidulans. evidence for oxygenase-catalyzed heme o/a transformation.	incubation of obligately photoautotrophic and aerobic cyanobacterium anacystis nidulans (synechococcus sp. pcc 6301) in the light in the presence of the photo-system ii inhibitor 3-(3,4-dichlorophenyl)-1,1-dimethylurea and equilibrated with approximately 1% (v/v) o2 in n2 (10 microm o2 in solution) led to a decrease of the heme a content of isolated cytoplasmic membranes and to the appearance of heme o. the latter was not seen in membranes from fully aerated cells (> 210 microm dissolved o2). no ...	1995	7499269
a novel operon organization involving the genes for chorismate synthase (aromatic biosynthesis pathway) and ribosomal gtpase center proteins (l11, l1, l10, l12: rplkajl) in cyanobacterium synechocystis pcc 6803.	many of the ribosomal protein (rp) genes in both bacterial and chloroplast genomes occur, for reasons not yet understood, in operons that include nonribosomal genes. here we report such an operon organization in a cyanobacterium (synechocystis pcc6803) involving the genes for four rps that are important in the gtpase function of the ribosome and the aroc gene encoding chorismate synthase, a key enzyme in the shikimate pathway for biosynthesis of aromatic amino acids and cell wall components. the ...	1993	7505271
a gene encoding a protein related to eukaryotic protein kinases from the filamentous heterocystous cyanobacterium anabaena pcc 7120.	protein kinases play essential roles in the development of eukaryotic cells. these enzymes display various degrees of sequence similarity in their catalytic domains. this conservation has allowed the identification of protein kinases in a variety of organisms, including the gram-negative bacterium myxococcus xanthus. in this study, sequences related to those encoding eukaryotic protein kinases were amplified by pcr from dna of anabaena pcc 7120, a filamentous cyanobacterium that differentiates c ...	1993	7505448
the existence of eukaryotic ribonucleoprotein consensus sequence-type rna-binding proteins in a prokaryote, synechococcus 6301.	a group of proteins containing a conserved ribonucleoprotein consensus sequence (rnp-cs)-type rna-binding domain (cs-rbd) of approximately 80 amino acids is present in eukaryotic cells and binds specifically to a wide variety of rna molecules. we have isolated 12 kda single-stranded dna binding proteins from the unicellular cyanobacterium synechococcus 6301. the amino-terminal sequence was determined and two distinct genomic clones were isolated from a synechococcus 6301 genomic library. sequenc ...	1994	7510387
organization and transcription of the class i phycoerythrin genes of the marine cyanobacterium synechococcus sp. wh7803.	the nucleotide sequences of the class i phycoerythrin (pe) alpha- and beta-subunit genes (cpea and cpeb) from the marine cyanobacterium synechococcus sp. wh7803 are reported. the cpeb gene is located upstream of cpea with a separation of 56 nucleotides and the two genes are co-transcribed as a transcript of 1.3 kb, with the transcription startpoint being localized to 110-111 bp upstream of cpeb. the sequence of the promoter region bears no similarity to promoters reported for other cyanobacteria ...	1994	7512390
sequence and structure of the rna subunit of rnase p from the cyanobacterium pseudoanabaena sp. pcc6903.	the catalytic rna subunit of ribonuclease p (rnase p) from the cyanobacterium pseudoanabaena sp. pcc6903 has been cloned and sequenced. the rna has a primary and secondary structure with overall similarity to other cyanobacterial rnase p rnas characterized so far but contains some peculiarities of its own. a consensus promoter sequence can be identified at the 5' end of the gene.	1994	7519449
evolutionary affiliation of the marine nitrogen-fixing cyanobacterium trichodesmium sp. strain nibb 1067, derived by 16s ribosomal rna sequence analysis.	the 16s rrna sequence of trichodesmium sp. strain nibb 1067 was determined and used for the construction of a distance tree and bootstrap analysis. the tree shows that, among the available cyanobacterial 16s rrna sequences, trichodesmium nibb 1067 has oscillatoria pcc 7515 as its closest relative, presenting 94.9% of sequence similarity with the latter strain. this is in contrast to a difference of 9 mol% g+c in mean genomic dna base composition between the two organisms. nevertheless, the genot ...	1994	7522848
cloning of omega 3 desaturase from cyanobacteria and its use in altering the degree of membrane-lipid unsaturation.	cyanobacteria respond to a decrease in temperature by desaturating fatty acids of membrane lipids to compensate for the decrease in membrane fluidity. among various desaturation reactions in cyanobacteria, the desaturation of the omega 3 position of fatty acids is the most sensitive to the change in temperature. in the present study, we isolated a gene, designated desb, for the omega 3 desaturase from the cyanobacterium, synechocystis sp. pcc 6803. the desb gene encodes a protein a 359 amino-aci ...	1994	7524725
targeted deletion of psaj from the cyanobacterium synechocystis sp. pcc 6803 indicates structural interactions between the psaj and psaf subunits of photosystem i.	photosystem i catalyzes the light-driven oxidation of plastocyanin or cytochrome c6 and the reduction of ferredoxin or flavodoxin. psaj is a 4.4 kda hydrophobic subunit of photosystem i from cyanobacteria and chloroplasts. to investigate the function of psaj, we generated a mutant strain of the cyanobacterium synechocystis sp. pcc 6803 in which the psaj gene is replaced by a gene for chloramphenicol resistance. deletion of psaj led to a reduction in the steady state rna level from psaf which is ...	1994	7524726
catalysis of rna cleavage by a ribozyme derived from the group i intron of anabaena pre-trna(leu).	in the cyanobacterium anabaena pcc7120, the precursor to trna(leu) contains a 249-nucleotide group i intron that undergoes efficient self-splicing in vitro. by deleting the 5' and 3' splice sites, this intron has now been converted to an rna enzyme that uses a guanosine nucleophile to cleave substrate rnas (s) with multiple turnover. this anabaena ribozyme has a second-order rate constant for rna cleavage (kcat/km)s that is 250-500-fold smaller than that of the tetrahymena ribozyme, and a multip ...	1994	7527660
in vitro replication of cyanobacterial plasmids from synechocystis pcc 6803.	little knowledge of dna replication in cyanobacteria is available. in this study, we report the development and characterization of an in vitro system for studies of replication of the endogenous plasmids from the unicellular cyanobacterium synechocystis 6803. this system (fraction iii) was isolated at high salt concentrations and partially purified on a heparin-agarose column. dna polymerases in synechocystis 6803 appeared to be associated with membranes and could be released by the addition of ...	1994	7531350
factors regulating cryivb expression in the cyanobacterium--synechococcus pcc 7942.	the expression of the larvicidal bacillus thuringiensis subsp. israelensis cryivb gene in cyanobacteria has been suggested to be an effective means of controlling mosquito populations. using a variety of cryivb constructs, in this study we have examined the effect of synechococcus pcc 7942 culture age on intracellular toxin levels and have attempted to determine the mechanisms by which cryivb gene expression is regulated. the data suggest that specific degradation of the cryivb mrna limits toxin ...	1995	7531814
requirement of the regulatory protein ntca for the expression of nitrogen assimilation and heterocyst development genes in the cyanobacterium anabaena sp. pcc 7120.	the cyanobacterial ntca gene encodes a dna-binding protein that belongs to the crp family of bacterial transcriptional regulators. in this work, we describe the isolation of an ntca insertional mutant of the dinitrogen-fixing, heterocyst-forming cyanobacterium anabaena sp. pcc 7120. the anabaena ntca mutant was able to use ammonium as a source of nitrogen for growth, but was unable to assimilate atmospheric nitrogen (dinitrogen) or nitrate. nitrogenase and enzymes of the nitrate reduction system ...	1994	7534371
bacterial luciferase as a reporter of circadian gene expression in cyanobacteria.	to allow continuous monitoring of the circadian clock in cyanobacteria, we previously created a reporter strain (amc149) of synechococcus sp. strain pcc 7942 in which the promoter of the psbai gene was fused to vibrio harveyi luciferase structural genes (luxab) and integrated into the chromosome. northern (rna) hybridization and immunoblot analyses were performed to examine changes in abundance of the luxab mrna, the native psbai mrna, and the luciferase protein to determine whether bioluminesce ...	1995	7536731
a family of cold-regulated rna-binding protein genes in the cyanobacterium anabaena variabilis m3.	i previously found a cold-regulated rna-binding protein gene rbpa (now named rbpa1) in anabaena variabilis m3 [sato, n. (1994) plant mol. biol. 24, 819-823]. i show here that this gene is a member of a gene family containing at least eight members as evidenced by southern blot and immunoblot analyses. i have isolated three additional genes (rbpb, rbpc and rbpd) in this family. of these, rbpb was 100% identical to the rbpb gene of anabaena 7120 reported previously. another gene named rbpa in anab ...	1995	7541909
the role of phosphatidylglycerol as a functional effector and membrane anchor of the d1-core peptide from photosystem ii-particles of the cyanobacterium oscillatoria chalybea.	the intrinsic polypeptide d1, isolated from photosystem (ps) ii-particles of the cyanobacterium oscillatoria chalybea, was obtained by electroelution and fractionated extraction with organic solvents. purification was demonstrated by western blotting and amino acid sequencing. by carrying out d1-immunization in rabbits a polyclonal monospecific d1-antiserum was obtained. for the qualitative characterization of d1 as a lipid-binding peptide, the effect of the lipids phosphatidylglycerol (pg), mon ...	1995	7546031
an independent role of cytochrome c-550 in cyanobacterial photosystem ii as revealed by double-deletion mutagenesis of the psbo and psbv genes in synechocystis sp. pcc 6803.	cytochrome (cyt) c-550 and the 33 kda protein are two extrinsic components that function in maintaining oxygen evolution in cyanobacterial cells. deletion of either of the two components has been shown to result in cyanobacterial phenotypes that are still capable of photoautotrophic growth albeit with a reduced rate. in order to study the function of cyt c-550 in cyanobacterial photosystem ii (psii) and its possible interaction with the 33 kda extrinsic protein, we constructed a mutant lacking b ...	1995	7548017
anatoxin-a is a potent agonist of the nicotinic acetylcholine receptor of bovine adrenal chromaffin cells.	(+)-anatoxin-a is a neurotoxic alkaloid produced by the cyanobacterium anabaena flos-aquae. in this study synthetic (+/-)-anatoxin-a was tested on isolated bovine adrenal chromaffin cells to determine its ability to evoke secretion of endogenous catecholamines through neuronal-type nicotinic receptor activation. anatoxin-a was found to act as a potent agonist of the secretory response of chromaffin cells with an ec50 of 1-2 microm, compared with an ec50 of 4-5 microm for nicotine. the cells resp ...	1995	7556413
molecular cloning and functional expression in e. coli of a novel plant enzyme mediating zeta-carotene desaturation.	we have cloned a cdna from the plant capsicum annuum which encodes a novel enzyme mediating the dehydrogenation of zeta-carotene and neurosporene to lycopene when expressed in e. coli cells accumulating zeta-carotene or neurosporene. this enzyme is unable to dehydrogenate either phytoene or lycopene. the deduced amino acid sequence suggests that this cdna encodes a polypeptide whose mature size is ca. 59 kda and which is synthesized as a precursor with a nh2-terminal extension resembling transit ...	1995	7556669
a novel insertion sequence (is)-like element of the thermophilic bacterium ps3 promotes expression of the alanine carrier protein-encoding gene.	a novel insertion sequence (is)-like element was found in the 5'-upstream region of the alanine carrier protein-encoding gene (acp) in the thermophilic bacterium ps3 chromosomal dna. the sequence contained an open reading frame (orf) encoding a polypeptide of 369 amino acids which revealed high similarity with orfs from is891 from the cyanobacterium anabaena and is1136 from saccharopolyspora erythraea. the direction of transcription was the same as that of acp, and typical inverted and direct re ...	1995	7557457
cloning and sequence of ftsz and flanking regions from the cyanobacterium anabaena pcc 7120.	using degenerate oligodeoxyribonucleotide primers based on conserved regions of the cell-division protein ftsz, a 220-bp fragment of dna was amplified by the polymerase chain reaction from anabaena pcc 7120 (ana). this fragment, which showed significant homology with escherichia coli ftsz, was used as a probe to isolate a 15-kb genomic clone containing ftsz from an ana dna library. sequence analysis revealed an open reading frame (orf) encoding a protein of 379 amino acids, with 49% identity wit ...	1995	7557485
circadian expression of the dnak gene in the cyanobacterium synechocystis sp. strain pcc 6803.	the expression of the dnak gene in the cyanobacterium synechocystis sp. strain pcc 6803 was continuously monitored as bioluminescence by an automated monitoring system, using the bacterial luciferase genes (luxab) of vibrio harveyi as a reporter of promoter activity. a dnak-reporting bioluminescent synechocystis strain was constructed by fusing a promoterless segment of the luxab gene set downstream of the promoter region of the synechocystis dnak gene and introduction of this gene fusion into a ...	1995	7559349
cloning, sequencing, and regulation of the glutathione reductase gene from the cyanobacterium anabaena pcc 7120.	glutathione reductase (gr) was purified from the cyanobacterium anabaena pcc 7120. a 3-kilobase genomic dna fragment containing the coding sequence for the gr gene (gor) was identified and cloned by polymerase chain reaction based on sequences of selected peptides isolated from proteolyzed gr. the coding sequence encompassing 458 amino acid residues, as well as 360 base pairs of the 5'-flanking region and 430 base pairs of the 3'-flanking region, were determined. genomic southern analysis indica ...	1995	7559423
characterization of the interaction of the marine cyanobacterial natural product curacin a with the colchicine site of tubulin and initial structure-activity studies with analogues.	curacin a, the major lipid constituent of a strain of the marine cyanobacterium lyngbya majuscula obtained off the coast of curaçao, is a potent antimitotic agent that we have previously shown to inhibit microtubule assembly and colchicine binding to tubulin. in the present study, we report that curacin a probably binds in the colchicine site because it competitively inhibits the binding of [3h]colchicine to tubulin with an apparent ki value of 0.6 microm and stimulates tubulin-dependent gtp hyd ...	1995	7565634
a second nitrogenase in vegetative cells of a heterocyst-forming cyanobacterium.	in many filamentous cyanobacteria nitrogen fixation occurs in differentiated cells called heterocysts. filamentous strains that do not form heterocysts may fix nitrogen in vegetative cells, primarily under anaerobic conditions. we describe here two functional mo-dependent nitrogenases in a single organism, the cyanobacterium anabaena variabilis. using a lacz reporter with a fluorescent beta-galactoside substrate for in situ localization of gene expression, we have shown that the two clusters of ...	1995	7568132