| identification of facultatively heterotrophic, n2-fixing cyanobacteria able to receive plasmid vectors from escherichia coli by conjugation. | plasmid vectors transferable by conjugation from escherichia coli to obligately photoautotrophic strains of anabaena spp. are also transferred to and maintained in heterotrophic, filamentous cyanobacteria of the genus nostoc. these organisms can be used for the genetic analysis of oxygenic photosynthesis, chromatic adaptation, nitrogen fixation, and heterocyst development. | 1985 | 3922953 |
| prokaryotic triterpenoids. 1. 3 beta-methylhopanoids from acetobacter species and methylococcus capsulatus. | 3 beta-methylbacteriohopanepolyol derivatives were isolated from three bacteria, acetobacter pasteurianus ssp. pasteurianus, methylococcus capsulatus and nostoc muscorum, and identified by spectroscopic methods and direct comparison with 3 beta-methyldiplopterol and 3 beta-methylhopan-29-ol synthesized from 22-hydroxyhopan-3-one. the 3 beta-methylhopanoid content of a. pasteurianus ssp. pasteurianus could be dramatically increased (up to 60% of the total hopanoid content) by addition of l-methio ... | 1985 | 3926494 |
| prokaryotic triterpenoids. 2. 2 beta-methylhopanoids from methylobacterium organophilum and nostoc muscorum, a new series of prokaryotic triterpenoids. | 2 beta-methylhopanoids, a new series of triterpenoids was identified from two prokaryotes. 2 beta-methyldiplopterol was isolated from the methylotrophic bacterium methylobacterium organophilum, and three different 2 beta-methylbacteriohopanepolyols from the cyanobacterium nostoc muscorum. the structures of these compounds was deduced by direct comparison with 2 beta-methyldiplopterol synthesized from 22-hydroxyhopan-3-one. | 1985 | 3926495 |
| cyanobiont diversity within and among cycads of one field site. | limited diversity was found among cyanobionts from a cultivated population of cycads at a field site in florida. all isolates were classified as nostoc but were different from the one nostoc species found in the soil. these cyanobacteria were root endophytes of several plants of zamia integrifolia and one of dioon. the isolates were similar morphologically and in their reactions to four fluorescein isothiocyanate conjugated lectins. electrophoretic protein profiles and zymograms distinguished on ... | 1992 | 1288849 |
| protein synthesis and proteolysis in immobilized cells of the cyanobacterium nostoc commune utex 584 exposed to matric water stress. | cells of the cyanobacterium nostoc commune utex 584 in exponential growth were subjected to acute water stress by immobilizing them on solid supports and drying them at a matric water potential (psi m) of -99.5 mpa. cells which had been grown in the presence of na235so4 before immobilization and rapid drying continued to incorporate 35s into protein for 90 min. this incorporation was inhibited by chloramphenicol. no unique proteins appeared to be synthesized during this time. upon further drying ... | 1985 | 3934134 |
| isolation and characterization of a virus infecting the blue-green alga nostoc muscorum. | | 1971 | 4108613 |
| light-induced oxidation-reduction reactions in a cell-free preparation from the blue-green alga nostoc muscorum: the role of cytochrome f, cytochrome b558, c550, and p700 in noncyclic electron transport. | | 1973 | 4148619 |
| possible respiratory sites in a blue-green alga nostoc sphaericum as demonstrated by potassium tellurite and tetranitro-blue tetrazolium reduction. | | 1969 | 4181442 |
| further evidence for a phycobilisome model from selective dissociation, fluorescence emission, immunoprecipitation, and electron microscopy. | phycobilisomes, isolated in 500 mm sorensen's phosphate buffer ph 6.8 from the red alga, porphyridium cruetum, were analyzed by selective dissociation at various phosphate concentrations. the results are consistent with a structural model consisting of an allophycocyanin core, surrounding by a hemispherical layer of r-phycocyanin, with phycoerythrin being on the periphery. such a structure also allows maximum energy transfer. intact phycobilisomes transfer excitation energy ultimately to a pigme ... | 1976 | 1276188 |
| ultrastructural development of nostoc muscorum a. | | 1973 | 4198641 |
| viability of lyophilized cyanobacteria (blue-green algae). | lyophilizatin of 13 cyanobacterial cultures belonging to seven genera was attempted in a variety of suspending substances. all organisms survived lyophilization when suspended in lamb serum. some of the organisms could be successfully lyophilized in horse serum, beef serum, fetal bovine serum, or human ascites fluid. with the exception of nostoc muscorium, none of the organisms survived lyophilization in skim milk medium, egg albumin medium, or jansen salts medium. | 1976 | 827240 |
| amino acid sequence of the major component of nostoc muscorum ferredoxin. | the amino acid sequence of the major component of ferredoxin isolated from a blue-green alga, nostoc muscorum, grown under n2 as the sole nitrogen source has been studied. the use of a combination of sequence analyzer, carboxypeptidases, and manual edman degradations on tryptic and chymotryptic peptides of carboxymethylferredoxin has established the amino acid seuqence, which consists of 98 amino acid residues. only four cysteine residues were present, located at positions 41, 46, 49, and 79. th ... | 1976 | 826526 |
| phycobilisomes in blue-green algae. | fifteen species of freshwater blue-green algae, including unicellular, filamentous, and colonial forms, were subjected to a variety of fixatives, fixation conditions, and stains for comparison of the preservation of phycobilisomes. absorption spectra of the corresponding in vivo and released photosynthetic pigments, in 10 of the species that were maintained in culture, demonstrated the presence of phycocyanin in all 10 species and phycoerythrin in only 2 of them. spectroscope and electron micros ... | 1974 | 4204443 |
| heterotrophic growth of the nitrogen fixing blue-green alga nostoc muscorum. | | 1974 | 4212052 |
| [nitrogen excretion by nitrogen fixing blue-green algae. i. growth of anabaena cylindriea and nostoc muscorum in various media, at different temperatures, and under light of different wavelengths (author's transl)]. | | 1973 | 4272180 |
| occurrence of cell lytic enzymes in blue-green bacteria. | detergent extracts of three blue-green bacteria (agmenellum quadruplicatum strain bg1, anacystis nidulans strain tx20, and nostoc sp. strain mac) contained enzymes capable of lysing suspensions of micrococcus lysodeikticus. the enzyme preparation from a. quadruplicatum released soluble reducing fragments from purified peptidoglycan. the lytic activity exhibited a ph optimum between 6 and 7, was relatively heat stable, and was susceptible to attack by proteolytic enzymes. these results extend the ... | 1973 | 4745432 |
| cytophaga that kills or lyses algae. | a myxobacterium (cytophaga n-5) isolated from sewage kills or lyses an array of living green and blue-green algae. when assayed with nostoc muscorum or plectonema boryanum, plaques form like those caused by the blue-green algal virus lpp-1. this isolate lyses or inhibits mutually gram-positive and gram-negative eubacteria. | 1969 | 4891858 |
| purification and properties of glycogen isolated from a blue-green alga, nostoc muscorum. | alpha granules were isolated from a blue-green alga, nostoc muscorum, in large quantities and high purity by sucrose density gradient centrifugation. sodium deoxycholate was used to eliminate membrane contamination. isolated alpha granules from this species have average dimension of 31 nm in width and 65 nm in length. each alpha granule consists of two equal parts. attempts to dissociate the intact granule under mild conditions into relatively large subunits did not succeed. analytical centrifug ... | 1971 | 4993320 |
| nitrogen metabolism of nostoc muscorum & phormidiu phormidium fragile. | | 1971 | 5004444 |
| fixation of elementary nitrogen by nostoc punctiforme (kütz.) hariot and scytonema bohneri schmidle in pure and unialgal cultures. | | 1970 | 5412270 |
| possible respiratory sites in a blue-green alga nostoc sphaericum as demonstrated by potassium tellurite and tetranitro-blue tetrazolium reduction. | | 1969 | 5779919 |
| induction by ultraviolet irradiation of mutation in the blue-green alga nostoc linckia (roth) born. et flah. | | 1969 | 5782614 |
| biosynthesis of alkanes in nostoc muscorum. | | 1969 | 5798100 |
| [fixation of molecular nitrogen by some representatives of the genera aanbaena and nostoc]. | | 1966 | 5995733 |
| the role of na2s in anoxygenic photosynthesis and h2 production in the cyanobacterium nostoc muscorum. | na2s is known to support anoxygenic photosynthesis in some strains of cyanobacteria and to stimulate h2 production in n2 fixing filaments of nostoc muscorum. we have shown electron transfer between na2s and photosystem i to be dependent on cytochrome b559 which was detected only in vegetative cells. an electron mediator was required to support na2s driven nitrogenase activity in isolated heterocysts. na2s was also found to deplete the atp pool, probably by inhibiting electron transfer from photo ... | 1984 | 6091649 |
| biochemical diversity for biosynthesis of aromatic amino acids among the cyanobacteria. | we examined the enzymology and regulatory patterns of the aromatic amino acid pathway in 48 strains of cyanobacteria including representatives from each of the five major grouping. extensive diversity was found in allosteric inhibition patterns of 3-deoxy-d-arabinoheptulosonate 7-phosphate synthase, not only between the major groupings but also within several of the generic groupings. unimetabolite inhibition by phenylalanine occurred in approximately half of the strains examined; in the other s ... | 1982 | 6119309 |
| mutation to resistance for virus n-1 in the blue-green alga nostoc muscorum. | the spontaneous and nitrosoguanidine induced n-1 virus resistant mutants of the blue-green alga nostoc muscorum were isolated with the average mutation frequency of 3.55 x 10(-5) and 6.08 x 10(-4) respectively. of the surviving colonies 8 per cent became virus sensitive,whereas out of the remaining 92 per cent 9.3 per cent showed lysogenic behaviour and 13.3 per cent showed poor or no nitrogen fixing ability. mutation to virus-resistance was independent of the presence of the virus.spontaneous h ... | 1976 | 826239 |
| effects of magnesium and chloride ions on light-induced electron transport in membrane fragments from a blue-green alga. | the effects of magnesium and chloride ions on photosynthetic electron transport were investigated in membrane fragments of a blue-green alga, nostoc muscorum (strain 7119), noted for their stability and high rates of electron transport from water or reduced dichlorophenolindophenol to nadp+. magnesium ions were required not only for light-induced electron transport from water to nadp+ but also for protection in the dark of the integrity of the water-photooxidizing system (photosystem ii). membra ... | 1976 | 813781 |
| carbon dioxide assimilation in blue-green algae: initial studies on the structure of ribulose 1,5-bisphosphate carboxylase. | d-ribulose 1,5-bisphosphate carboxylase was purified from the blue-green alga anabaena cylindrica (lemm) by procedures involving acid precipitation, ammonium sulfate fractionation, and sephadex g-200 gel filtration. the enzyme was homogeneous by the criterion of polyacrylamide disc gel electrophoresis and was a multimer of a single-size polypeptide chain of 54,000 daltons. the carboxylases from four species of blue-green algae (anabaena, nostoc strain mac, agmenellum quadruplicatum strain pr-6, ... | 1976 | 812868 |
| nostoc pcc7524, a cyanobacterium which contains five sequence-specific deoxyribonucleases. | five nucleotide sequence-specific deoxyribonucleases present in cell-free extracts of the filamentous cyanobacterium nostoc pcc7524 have been purified and characterized. one of these enzymes, designated nsp(7524)i cleaves at a new kind of nucleotide sequence, i.e. 5'-pucatg py-3'. the other four restriction enzymes in this organism, designated nsp(7524)ii, nsp(7524)iii, nsp(7524)iv and nsp(7524)v, are isoschizomers of enzymes which have been previously described. the cleavage site of nsp(7524)ii ... | 1982 | 6298063 |
| a restriction map of plasmid pdc1 from the filamentous cyanobacterium nostoc sp. mac pcc 8009. | a plasmid designated pdc1 from the cyanobacterium nostoc sp. mac pcc 8009 was incubated with 16 different restriction enzymes, of which 8 cleaved pdc1. plasmid pdc1 has a single site for clai, two sites for each of bgli, ecori, ecorv, and mlui, three sites for hpai, and four for hindiii. a restriction map of pdc1 for these 7 enzymes was constructed. | 1983 | 6314412 |
| effect of four heavy metals on the biology of nostoc muscorum. | this study presents the effects of cr, pb, ni and ag on growth, pigments, protein, dna, rna, heterocyst frequency, uptake of nh4+ and no3-, loss of electrolytes (na+ and k+), nitrate reductase and glutamine synthetase activities of nostoc muscorum. the statistical tests revealed a direct positive correlation between the metal concentration and inhibition of different processes. ni was found to be more toxic against growth, pigments and heterocyst differentiation compared to the other metals. inh ... | 1990 | 1975195 |
| isolation and characterization of gas vesicles from microcyclus aquaticus. | intact gas vesicles of microcyclus aquaticus s1 were isolated by using centrifugally accelerated flotation of vesicles and molecular sieve chromatography. isolated gas vesicles were cylindrical organelles with biconical ends and measured 250x100nm. the gas vesicle membrane was composed almost entirely of protein; neither lipid nor carbohydrate was detected, although one mole of phosphate per mole of protein was found. amino acid analysis indicated that the protein contained 54.6% hydrophobic ami ... | 1977 | 403898 |
| oxidative phosphorylation and energy buffering in cyanobacteria. | the onset of respiration in the cyanobacteria anacystis nidulans and nostoc sp. strain mac upon a shift from dark anaerobic to aerobic conditions was accompanied by rapid energization of the adenylate pool (owing to the combined action of atp synthase and adenylate kinase) and also the guanylate, uridylate, and cytidylate pools (owing to nucleoside diphosphate and nucleoside monophosphate kinases). rates of the various transphosphorylation reactions were comparable to the rate of oxidative phosp ... | 1986 | 3023299 |
| analysis of fluorescence kinetics and energy transfer in isolated alpha subunits of phycoerythrin from nostoc sp. | | 1986 | 3081920 |
| metabolic activities of isolated akinetes of the cyanobacterium nostoc spongiaeforme. | intact akinetes (spores) of the cyanobacterium nostoc spongiaeforme can be isolated free of vegetative cells and heterocysts. the akinetes remain viable for at least 2 weeks in distilled water. they do not germinate in water but do so readily when transferred subsequently to cyanobacterial growth medium. isolated, nongerminating akinetes incorporated 35s from na235so4 into protein and lipid. similar incorporation was observed when akinetes were isolated from old cultures (containing primarily ak ... | 1983 | 6413494 |
| isolation of polysomes from nostoc sp. mac and translation of messenger rna in a heterologous cell-free system. | a method has been established which isolated polysomes from the lysozyme/edta-shocked cyanobacterium, nostoc sp. mac. in a typical preparation the total recovery of rna as polysomes was 83%, in which 77% of the polysome fraction was present at sizes greater than 5-mers and 23% as 2-4-mers. messenger rna isolated from such a preparation of polysomes produced a 10-fold stimulation in the incorporation of [35s]methionine into polypeptides by a cell-free system of escherichia coli. the in vitro-synt ... | 1983 | 6415228 |
| transfer of nitrate reductase genes of the cyanobacterium nostoc muscorum into rhizobium japonicum. | transformation of rhizobium japonicum cb1809 was studied using dna from the cyanobacterium nostoc muscorum atcc 27893. a spontaneous nitrate reductase deficient (nar-) mutant (nr-6) of r. japonicum cb1809 was isolated with a frequency of 8.4 x 10(-7). streptomycin (sm) and neomycin (neo) resistance markers were introduced into strain nr-6, and the resulting strain was designated nr-6 smr neor. experiments with cyanobacterial dna and live cells of strain nr-6 smr neor indicated transformation of ... | 1983 | 6415231 |
| effect of tryptophan on 2,4-dichlorophenoxyacetic acid toxicity in the nitrogen-fixing-cyanobacterium nostoc linckia. | the combined effect of a hormone weed killer 2,4-dichlorophenoxyacetic acid (2,4-d) and an amino acid (tryptophan) has been studied on growth and heterocyst differentiation in the cyanobacterium nostoc linckia. 2.4-d at 100 micrograms/ml stimulated growth and heterocyst frequency in combined nitrogen-free medium while its higher concentrations inhibited both. tryptophan under similar conditions promoted much growth yield with 3-4 fold enhanced heterocyst frequency than the control. such heterocy ... | 1986 | 3083089 |
| production, by filamentous, nitrogen-fixing cyanobacteria, of a bacteriocin and of other antibiotics that kill related strains. | colonies of sixty-five filamentous cyanobacteria were screened for the production of temperate phages and/or antibiotics on solid medium. none of them was observed to release phages. however, seven n2-fixing strains were found to produce antibiotics very active against other cyanobacteria. the antibiotic produced by nostoc sp. 78-11a-e represents a bacteriocin of low molecular weight. nostoc sp. atcc 29132 appears to secrete, together with an antibiotic, a protein that inhibits its action. | 1986 | 3094472 |
| influence of cypermethrin and fenvalerate on a green alga and three cyanobacteria isolated from soil. | the effects of two pyrethroid insecticides, cypermethrin and fenvalerate, on a green alga (scenedesmus bijugatus) and three species of cyanobacteria (synechococcus elongatus, nostoc linckia, and phormidium tenue), all isolated from a black cotton soil, were studied using either cell number or chlorophyll a as toxicity criterion. all the four species were either unaffected or stimulated at 5 micrograms ml-1. of the two insecticides, cypermethrin, at 10 to 50 micrograms ml-1, inhibited s. bijugatu ... | 1987 | 3121278 |
| effect of insecticides and phenolics on nitrogen fixation by nostoc linckia. | | 1988 | 3145048 |
| powerful mutagenicity of a bipyridylium herbicide in a nitrogen-fixing blue-green alga nostoc muscorum. | the herbicide, paraquat (1,1'-dimethyl-4,4'-bipyridylium ion), was found to be toxic and lytic to nostoc muscorum in n2 (at the expense of elemental nitrogen, i.e. unsupplemented with any combined nitrogen source) and no-3 media, without any apparent inhibitory or stimulatory effect on its nitrogen-fixing apparatus, i.e. heterocyst formation. at a dose of paraquat resulting in 20, 50 and 75% survival, induction of reverse mutations (from het- nif- auxotrophy to het+ nif+ prototrophy), forward mu ... | 1984 | 6436694 |
| 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 |
| the role of glutathione and ascorbate in hydroperoxide removal in cyanobacteria. | the antioxidative potential of cyanobacteria to scavenge hydroperoxides formed as by-products of photosynthetic activity was investigated in nostoc muscorum 7119 and synechococcus 6311. these cells contained a high concentration of glutathione, 2-5 mm, and a low concentration of ascorbate, 20-100 um. no glutathione peroxidase was detected while the activity of ascorbate peroxidase was high, reacting with hydrogen peroxide, t-butyl hydroperoxide, and cumene hydroperoxide. dehydroascorbate reducta ... | 1985 | 3933503 |
| role of reduced exogenous organic compounds in the physiology of the blue-green bacteria (algae): photoheterotrophic growth of a "heterotrophic" blue-green bacterium. | nostoc sp. (strain mac) was shown to be capable of using glucose, fructose, or sucrose as a sole source of carbon and energy in the dark. in the light in the absence of exogenously supplied co(2), this strain exhibited a more versatile metabolism. in addition to the three sugars above, glycerol and acetate served as sole sources of carbon. this photoheterotrophic growth in the absence of exogenously supplied co(2) appears to involve o(2)-evolving photosynthesis. the action spectrum for photohete ... | 1973 | 4196252 |
| apoflavodoxin aggregation following dissociation of flavin. | flavodoxins were isolated for the cyanobacteria anacystis nidulans and nostoc strain mac, and from the red alga chondrus crispus, and apoflavodoxins prepared by five methods. gel electrophoretic studies showed that whereas the apoproteins of a. nudulans and nostoc strain mac were recovered in monomeric form, the removal of riboflavin 5'-phosphate from c. crispus flavodoxin resulted in extensive aggregation of the apoprotein. in extent and nature this aggregation differed with the dissociating ag ... | 1980 | 6774761 |
| cell size and heterocyst differentiation in nostocacean blue-green algae. | cell size variations in three heterocystous blue-green algae, viz. nostoc muscorum (isu strain), n. muscorum (uw strain) and n. calcicola (a local isolate) have been surveyed under conditions permissive and non-permissive of heterocyst differentiation. a monomodal distribution pattern was observed for the two strains of n. muscorum under conditions not requiring heterocyst differentiation, while elemental nitrogen grown cultures retained a group of relatively larger cells in addition to this mod ... | 1980 | 6775879 |
| 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 |
| differentiation in nostoc muscorum: nitrogenase is synthesized in heterocysts. | cellular differentiation can be observed in certain filamentous blue-green algae after transfer of the cells from medium containing nh(4) (+) or no(3) (-) to nitrogen-free medium. the appearance of differentiated cells (heterocysts) is accompanied by an increase in the activity of nitrogenase, an enzyme complex that reduces n(2) to nh(3). we have separated vegetative cells from heterocysts in differentiated filaments of nostoc muscorum, and analyzed their proteins by polyacrylamide-gel electroph ... | 1973 | 4200722 |
| two plant-type ferredoxins from a blue-green alga, nostoc verrucosum. | two plant-type ferredoxins were isolated and purified from a blue-green alga, nostoc verrucosum. they were separable by chromatography on a deae-cellulose column. the slow-moving band was designated ferredoxin i (fd i) and the fast-moving band was ferredoxin ii (fd ii). the ratio of the yield of ferredoxins i and ii was about 1 : 0.84. both ferredoxins had absorption spectra similar to those of plant-type ferredoxins. two atoms of non-heme iron and two of labile sulfur were found per mol of both ... | 1977 | 403941 |
| 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 |
| amino acid sequences of nostoc strain mac ferredoxins i and ii. | the amino acid sequences of ferredoxins i and ii from a blue-green alga, nostoc strain mac were determined. this alga is able to grow autotrophically in the light or heterotrophically in the dark. analyses of tryptic peptides of cm-proteins by conventional methods including solid-phase edman degradation gave the complete amino acid sequences. both molecules consisted of 98 amino acid residues and 34 amino acid differences including two deletions were found between the two. comparing these sequen ... | 1982 | 6818220 |
| evidence for two types of p-700 in membrane fragments from a blue-green alga. | the mathematical analysis described in the preceding paper (biochim. biophys. acta (1977) 460, 65-75), in which the steady-state photooxidation of p-700 was compared with overall electron flux in photosystem i chloroplast fragments, was applied to membrane fragments from the blue-gree alga nostoc muscorum (strain 7119) noted for their high activity of both photosystem i and photosystem ii. the same analysis, which gave good agreement between the photooxidation of p-700 and the overall light-indu ... | 1977 | 403940 |
| allophycocyanin from nostoc sp. phycobilisomes. properties and amino acid sequence at the nh2 terminus of the alpha and beta subunits of allophycocyanins i, ii, and iii. | allophycocyanin from nostoc sp. phycobilisomes was separated into four spectrally distinct components designated allophycocyanin i, b, ii, and iii by adsorption chromatography on brushite columns. allophycocyanins i and b had red-shifted fluorescence emission maxima, and on this basis, may function in transfer of excitation energy from phycobilisomes to chlorophyll a. allophycyanins ii and iii, which together comprise 70% of the total allophycocyanin, have absorption maxima at 648 nm and 650 nm, ... | 1980 | 7410430 |
| 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 |
| structure and evolution of paramecium hemoglobin genes. | hemoglobin (hb) genes have been cloned from three different species of ciliated protists, p. multimicronucleatum, p. triaurelia and p. jenningsi. southern blotting of the genomic dnas using the p. caudatum hb cdna showed both intraspecies variation in different stocks of p. caudatum and interspecies variation within the genus paramecium. the isolated hb genes were composed of 118, 117 and 117 codons, and interrupted by a short intron with 27, 29 and 29 bp at the same position, in p. multimicronu ... | 1995 | 7578257 |
| two heterocyst-specific dna rearrangements of nif operons in anabaena cylindrica and nostoc sp. strain mac. | two site-specific dna rearrangements occur during heterocyst differentiation in the cyanobacterium anabaena sp. strain pcc 7120: the deletion of an 11 kb element from within the nifd gene and the deletion of a 55 kb element from within the fdxn gene. three nostoc and six anabaena strains were screened for the presence of the nifd and fdxn elements by southern hybridization with anabaena pcc 7120 dna probes. eight of the nine strains contained dna sequences that were similar to the nifd element. ... | 1995 | 7582007 |
| structural and chemical properties of a flavodoxin from anabaena pcc 7119. | structural and chemical properties of a flavodoxin from anabaena pcc 7119 are described. the first 36 residues of the amino-terminal amino acid sequence have been determined and show extensive homology with flavodoxins isolated from other sources. anabaena flavodoxin exhibits a net negative change (-3) in the helix-1 segment as found with other cyanobacterial flavodoxins synechococcus 6301 (anacystis nidulans) and nostoc mac, but in contrast to the net positive charge found in this region in the ... | 1990 | 2119231 |
| genetic evidence of a major role for glucose-6-phosphate dehydrogenase in nitrogen fixation and dark growth of the cyanobacterium nostoc sp. strain atcc 29133. | heterocysts, sites of nitrogen fixation in certain filamentous cyanobacteria, are limited to a heterotrophic metabolism, rather than the photoautotrophic metabolism characteristic of cyanobacterial vegetative cells. the metabolic route of carbon catabolism in the supply of reductant to nitrogenase and for respiratory electron transport in heterocysts is unresolved. the gene (zwf) encoding glucose-6-phosphate dehydrogenase (g6pd), the initial enzyme of the oxidative pentose phosphate pathway, was ... | 1995 | 7592384 |
| characterization of ts-mutants of cyanophage n-1 by their inactivation by physical and chemical agents. | the effect of temperature, ultraviolet (uv) light and ethylenediaminetetraacetic acid (edta) on the stability of cyanophage n-1, infecting the cyanobacterium nostoc muscorum was studied. complete inactivation of the phage occurred at 60 degrees c in 6 mins. all the temperature-sensitive (ts) mutants exhibited faster inactivation at 50 degrees c than the wild type. uv light readily inactivated the particles of the wild giving a survival of 3.44% at a dose of 60 secs. all the ts-mutants were found ... | 1995 | 7676938 |
| a protein-tyrosine/serine phosphatase encoded by the genome of the cyanobacterium nostoc commune utex 584. | protein-tyrosine phosphorylation has long been regarded as an exclusively eukaryotic phenomenon. although some non-eukaryotes, mainly viruses, possess genes encoding protein-tyrosine kinases or protein-tyrosine phosphatases, these were probably appropriated from the eukaryotic hosts that constitute the sites of action of these enzymes. herein we identify a gene, iphp, from the chromosome of the cyanobacterium nostoc commune utex 584 that contains the his-cys-xaa-ala-gly-xaa-xaa-arg sequence char ... | 1993 | 7681825 |
| structure of a novel oligosaccharide-mycosporine-amino acid ultraviolet a/b sunscreen pigment from the terrestrial cyanobacterium nostoc commune. | water-soluble uv-a/b-absorbing pigments are secreted by cells of the cosmopolitan terrestrial cyanobacterium nostoc commune. the pigments constitute a complex mixture of monomers with molecular masses of up to 1801 da. two different chromophores with absorption maxima at 312 and 335 nm are linked to different amino acids and to oligosaccharides consisting of galactose, glucose, xylose, glucuronic acid, and glucosamine. the 335 nm chromophore is a 1,3-diaminocyclohexen derivative, while the chrom ... | 1995 | 7721752 |
| reconstitution of electron transport in photosystem i with psac and psad proteins expressed in escherichia coli. | a fusion protein, denoted psac1, which contains an amino-terminal extension of five amino acids (mehsm...) and is derived from an in vitro modified form of the psac gene of synechococcus sp. pcc 7002, has been over-expressed in escherichia coli. the product of the psad gene of nostoc sp. pcc 8009 has similarly been over-expressed. the psac1 and psad proteins can be combined with the photosystem i core protein of synechococcus sp. pcc 6301 to reconstitute electron transport from p700 to the termi ... | 1990 | 2125006 |
| toxicity of three herbicides to some nitrogen-fixing cyanobacteria. | the effects of some common rice field herbicides, such as 2,4-dichlorophenoxyacetic acid (2,4-d), machete, and saturn, on the paddy field nitrogen-fixing cyanobacteria nostoc linckia, nostoc calcicola, nostoc sp., and anabaena doliolum were studied. these cyanobacteria were found to be more tolerant to 2,4-d (lethal doses 1500-2000 micrograms/ml) than to machete and saturn (lethal doses 6-8 micrograms/ml). the effects of these three herbicides on some physiological processes of n. linckia were s ... | 1989 | 2500323 |
| plasmid and chromosomal dna recovery by electroextraction of cyanobacteria. | high voltage electroporation has been investigated as a method for rapid recovery of plasmid and chromosomal dna from the cyanobacteria nostoc pcc 7121, synechococcus pcc 7002, and anabaena pcc 7120. pulses of 18 kv/cm and higher applied to concentrated nostoc cells carrying a shuttle plasmid (prl25) resulted in copious release of nucleic acids and phycobiliproteins into the suspending medium. small portions of these supernatants, when electroporated with escherichia coli, gave rise to hundreds ... | 1995 | 7781980 |
| nitrogen fixation (nif) genes of the cyanobacterium anabaena species strain pcc 7120. the nifb-fdxn-nifs-nifu operon. | a second nitrogen fixation (nif) operon in the cyanobacterium (blue-green alga) anabaena (nostoc) sp. strain pcc 7120 has been identified and sequenced. it is located just upstream of the nifhdk operon and consists of four genes in the order nifb, fdxn, nifs, and nifu. the three nif genes were identified on the basis of their similarity with the corresponding genes from other diazotrophs. the fourth gene, fdxn, codes for a bacterial type ferredoxin (mulligan, m. e., buikema, w. j., and haselkorn ... | 1989 | 2553733 |
| regulation of expression of glutamine synthetase in a symbiotic nostoc strain associated with anthoceros punctatus. | a characteristic of n2-fixing cyanobacteria in symbiotic associations appears to be release of n2-derived nh4+. the specific activity of the primary ammonium-assimilating enzyme, glutamine synthetase (gs), was found to be three- to fourfold lower in nostoc sp. strain 7801 grown in symbiotic association with the bryophyte anthoceros punctatus than in free-living nostoc sp. strain 7801. quantitative immunological assays with antisera against gs purified from nostoc sp. strain 7801 and from escheri ... | 1987 | 2884210 |
| glutamine synthetase specific activity and protein concentration in symbiotic anabaena associated with azolla caroliniana. | glutamine synthetase (gs) is the primary nh4+ assimilating enzyme of cyanobacteria. the specific activities and cellular protein concentration of gs in symbiotic cyanobacteria associated with the water fern azolla caroliniana were determined and compared to free-living cultures of nostoc sp. strain 7801, a strain originally isolated from symbiotic association with the bryophyte anthoceros punctatus. both the in vitro specific activity and concentration of gs in symbiotic cyanobacteria separated ... | 1988 | 2902827 |
| transposon mutagenesis of nostoc sp. strain atcc 29133, a filamentous cyanobacterium with multiple cellular differentiation alternatives. | nostoc sp. strain atcc 29133 (pcc 73102; nostoc 29133) is a symbiotically-competent, facultatively heterotrophic, diazotrophic cyanobacterium with the capacity to differentiate specialized cells such as heterocysts, akinetes and hormogonial filaments. we have optimized several methods for physiological and molecular genetic analysis of nostoc 29133. by use of a tn5 derivative, tn5-1063 (km(r)bm(r)sm(r)), delivered by conjugation from escherichia coli, antibiotic-resistant mutants of nostoc 29133 ... | 1994 | 7881544 |
| sequence of a 2.6-kb cryptic plasmid from a marine cyanobacterium synechococcus sp. | we have shown previously that the copy number of plasmid psy10 from the marine cyanobacterium synechococcus sp. nkbg 042902 is dependent on the salinity of the growth medium. we report here the complete nucleotide sequence (2561 bp) of this plasmid. the longest open reading frame, orf-b (1.08 kb), occurs on a 1.6-kb ecori fragment. this orf encodes a putative protein which is 360 aa residues in length and is 37.8% homologous to the replication protein of plasmid pca2.4 from synechocystis sp. str ... | 1994 | 7899510 |
| a low potential iron-sulfur cluster bound to membranes in blue-green algae. | a new low temperature epr signal at g = 1.92 was found in photoreduced membrane fractions prepared from blue-green algae, nostoc muscorum, tolypothrix tenuis, phormidium persicinum, and anabaena variabilis. the signal also appeared when the sample was chemically reduced in the dark. judging from the spectrum, the signal was probably due to the reduced form of a membrane-bound iron-sulfur cluster, tentatively designated as cluster d. the midpoint potential of cluster d was determined to be -0.27 ... | 1985 | 2987203 |
| regulation of nostoc sp. phycobilisome structure by light and temperature. | nostoc sp. strain mac cyanobacteria were green in color when grown in white light at 30 degrees c and contained phycobilisomes that had phycoerythrin and phycocyanin in a molar ratio of 1:1. cells grown for 4 to 5 days in green light at 30 degrees c or white light at 39 degrees c turned brown and contained phycoerythrin and phycocyanin in a molar ratio of greater than 2:1. in addition to the change in pigment composition, phycobilisomes from brown cells were missing a 34.5-kilodalton, rod-associ ... | 1983 | 6411691 |
| cloning and nucleotide sequence of the gene encoding dinitrogenase reductase (nifh) from the cyanobacterium nostoc 6720. | the nucleotide sequence of the 3' end of the nifu coding sequence, the complete coding sequence of nifh and a substantial part of the 5' end of nifd coding sequence from nostoc 6720 is presented. the coding sequences are highly conserved with those of anabaena 7120 and anabaena sp. l31. however the intergenic region between nifu and nifh contains two segments of short tandemly repetitive repeat sequences (strrs) that differ from the strr that is common to both anabaena7120 and anabaenasp. l31. v ... | 1994 | 7918657 |
| two mutations that block heterocyst differentiation have different effects on akinete differentiation in nostoc ellipsosporum. | evident differentiation of vegetative cells into heterocysts in anabaena sp. strain pcc 7120 is prevented by insertions in genes hetr and hetp. nostoc ellipsosporum possesses single copies of genes that hybridize with hetr and hetp. in mutant ne2 of n. ellipsosporum, in which hetr is interrupted by an insert, and in a double recombinant of wild-type n. ellipsosporum with a plasmid that bears an interrupted copy of hetr, neither heterocysts nor akinetes are formed. when an intact copy of hetr fro ... | 1994 | 7934891 |
| inhibition of photosystem ii of nitrogen-fixing blue-green alga nostoc linckia by the rice-field herbicide benthiocarb. | effects of rice-field herbicide benthiocarb (s(4-chlorobenzyl)-n,n-diethyl thiolcarbamate) was studied on the nitrogen-fixing blue-green alga nostoc linckia. the herbicide caused inhibition of growth and heterocyst formation, an increase in intensity of photoacoustic signals, and a four-fold reduction in oxygen evolution, but did not affect dark o2-uptake. the inhibition of growth and heterocyst formation was relieved by 500 micrograms/ml glucose. a het-nif- mutant of nostoc muscorum failed to s ... | 1983 | 6415936 |
| athermal physiological effects of microwaves on a cynobacterium nostoc muscorum: evidence for em-memory bits in water. | athermal physiological effects of continuous wave and modulated microwaves were studied on a cynobacterium nostoc muscorum. the study shows that different microwave frequencies in continuous wave and modulated modes produced significantly different physiological effects on the algae. water-mediated bioeffects further present additional proof that water has the capability to remember the imposed electromagnetic field characteristics for an extended period of time. | 1994 | 8022214 |
| analysis of the sequences within and flanking the cyanoglobin-encoding gene, glbn, of the cyanobacterium nostoc commune utex 584. | a 3.5-kb segment of dna containing nifu glbn nifh nifd was cloned from a gene library of nostoc 584 and sequenced. the nifu-glbn intergenic region contains short tandemly repeated repetitive sequences (5'-aattacg). a sequence corresponding to a nifa-like upstream activator sequence (with the consensus recognition sequence for bifa in anabaena 7120), elements of a nifh promoter and a sequence that may function as a transcription terminator, were identified downstream from glbn. glbn, unique to ce ... | 1994 | 8063099 |
| [fractionation of phycobilisomes from the blue-green alga nostoc muscorum]. | phycobilisomes (pbs) isolated from nostoc muscorum contain eight spectral forms of phycobiliproteins. pbs partially dissociated by osmotic or temperature shock, were separated into 42s and 34s particles by centrifugation in sucrose density gradient. the 42s particles are enriched with phycocyanin, the 34s ones--with allophycocyanin. the 42s particles dissociate to free pigments by repeated osmotic or temperature shock and the 34s ones dissociate to subparticles i and ii having the constant pigme ... | 1984 | 6423967 |
| energetics of cyanophage n-1 multiplication in the diazotrophic cyanobacterium nostoc muscorum. | cyanophage n-1 multiplication was investigated during the latent period of the virus, when 14co2 fixation was inhibited whereas respiratory o2 uptake increased approximately 67% at 4 h after infection. a simultaneous decrease (70%) in the glycogen content of infected cells indicated its catabolic involvement. a chloramphenicol-sensitive rise in glucose-6-phosphate dehydrogenase activity as a result of n-1 infection partly explained the increase in aerobic respiration. the total atp pool declined ... | 1994 | 8078415 |
| the gene encoding cytochrome-c oxidase subunit i from synechocystis pcc6803. | the gene (coxi or coxa) encoding subunit i (coi) of cytochrome-c oxidase (cytochrome aa3) of synechocystis pcc6803, synechococcus pcc7942 (anacystis nidulans r2) and nostoc pcc8002 (nostoc mac), was identified by heterologous hybridization of chromosomal digests with a 17-bp oligodeoxyribonucleotide (probe c) derived from the coxi of paracoccus denitrificans. a single genomic fragment was found to bind to probe c in all chromosomal digests. due to its favorable signal-to-noise ratio, the genome ... | 1994 | 8125290 |
| water stress proteins of nostoc commune (cyanobacteria) are secreted with uv-a/b-absorbing pigments and associate with 1,4-beta-d-xylanxylanohydrolase activity. | acidic water stress polypeptides (wsp) with molecular masses of 33, 37 and 39 kda are the most abundant soluble proteins in the cyanobacterium nostoc commune. wsp polypeptides and uv-a/b-absorbing pigments are secreted by cells, accumulate in the extracellular glycan sheath, and are released from desiccated colonies upon rehydration. no evidence was obtained for either glycosylation, phosphorylation, or acylation of wsp polypeptides. nh2-terminal amino acid sequences of the 33-, 37-, and 39-kda ... | 1994 | 8125999 |
| redox potentials of algal and cyanobacterial flavodoxins. | the redox potentials of flavodoxins from the cyanobacteria synechococcus pcc 6301 (formerly anacystis nidulans) and nostoc strain mac, and from the red alga chondrus crispus, were determined by potentiometric titration. for the oxidized-semiquinone interconversion the potentials at ph 7.0 of the three flavodoxins were between -210 and -235 mv, and these were ph-dependent over the range ph 6.9-8.2. for the semiquinone-reduced interconversion the potentials of the cyanobacterial flavodoxins were c ... | 1984 | 6424653 |
| detection and characterization of cyanobacterial nifh genes. | the dna sequence of a 359-bp fragment of nifh was determined for the heterocystous strains anabaena sp. strain ca (atcc 33047), nostoc muscorum utex 1933, a nostoc sp., gloeothece sp. strain atcc 27152, lyngbya lagerheimii utex 1930, and plectonema boryanum iu 594. results confirmed that the dna sequence of the 359-bp segment is sufficiently variable to distinguish cyanobacterial nifh genes from other eubacterial and arachaeobacterial nifh genes, as well as to distinguish heterocystous from nonh ... | 1994 | 8161180 |
| [energy migration in phycobilisomes]. | fluorescence emission and polarization spectra of the phycobilisomes (pbs) of the blue-green alga nostoc muscorum were measured at 20, -73 and -196 degrees c while exciting at the absorption maximum of each pigment in the pbs. the emission spectra were deconvoluted into a number of gaussian components and energy migration coefficients and quantum yields of fluorescence for the 8 forms of the phycobilins constituting the pbs were calculated. the overlap integrals and the critical and real distanc ... | 1984 | 6425643 |
| components and activity of the photosynthetic electron transport system of intact heterocysts isolated from the blue-green alga nostoc muscorum. | heterocysts of the blue-green alga nostoc muscorum have been isolated by prolonged treatment with lysozyme. quantitative data are presented which show the occurrence of cytochromes c-553, f-557 and b-563 in heterocysts in amounts comparable to vegetative cells. particularly the content of the water-soluble cytochrome c-553 can be used to evaluate the intactness of a heterocyst preparation. cytochrome f-557 has been partially purified and found to be a c-type cytochrome corresponding to cytochrom ... | 1980 | 6772215 |
| spectral analysis of allophycocyanin i, ii, iii and b from nostoc sp. phycobilisomes. | low temperature (-196c) and room temperature (25c) absorption spectra of a family of allophycocyanin spectral forms isolated from nostoc sp. phycobilisomes as well as of the phycobilisomes themselves have been analyzed by gaussian curve-fitting. allophycocyanin i and b share long wavelength components at 668 and 679 nm, bands that are absent from allophycocyanin ii and iii. these long wavelength absorption components are apparently responsible for the 20 nm difference between the 680 nm fluoresc ... | 1980 | 6773565 |
| structure, composition, and assembly of paracrystalline phycobiliproteins in synechocystis sp. strain bo 8402 and of phycobilisomes in the derivative strain bo 9201. | the phycobiliproteins of the unicellular cyanobacterium synechocystis sp. strain bo 8402 and its derivative strain bo 9201 are compared. the biliproteins of strain bo 8402 are organized in paracrystalline inclusion bodies showing an intense autofluorescence in vivo. these protein-pigment aggregates have been isolated. the highly purified complexes contain phycocyanin with traces of phycoerythrin, corresponding linker polypeptides lr35pc and lr33pe (the latter in a small amount), and a unique col ... | 1994 | 8300542 |
| an osmotic stress protein of cyanobacteria is immunologically related to plant dehydrins. | dehydrins are a family of desiccation proteins that were identified originally in plants (t.j. close, a.a. kortt, p.m. chandler [1989] plant mol biol 13: 95-108; g. galau, t.j. close [1992] plant physiol 98: 1523-1525). dehydrins are characterized by the consensus amino acid sequence domain ekkgimdkikeklpg found at or near the carboxy terminus; the core of this domain (kikeklpg) may be repeated from one to many times within the complete polypeptide. dehydrins generally accumulate in plants in re ... | 1993 | 8310057 |
| a small plasmid, pca2.4, from the cyanobacterium synechocystis sp. strain pcc 6803 encodes a rep protein and replicates by a rolling circle mechanism. | different cryptic plasmids are widely distributed in many strains of cyanobacteria. a small cryptic plasmid, pca2.4, from synechocystis strain pcc 6803 was completely sequenced, and its replication mode was determined. pca2.4 contained 2,378 bp and encoded a replication (rep) protein, designated repa. an analysis of the deduced amino acid sequence revealed that repa of pca2.4 has significant homology with rep proteins of pkym from shigella sonnei, a pub110 plasmid family from gram-positive bacte ... | 1993 | 8320214 |
| regulation of nitrate reductase levels in the cyanobacteria anacystis nidulans, anabaena sp. strain 7119, and nostoc sp. strain 6719. | the effect of the nitrogen source on the cellular activity of ferredoxin-nitrate reductase in different cyanobacteria was examined. in the unicellular species anacystis nidulans, nitrate reductase was repressed in the presence of ammonium but de novo enzyme synthesis took place in media containing either nitrate or not nitrogen source, indicating that nitrate was not required as an obligate inducer. nitrate reductase in a. nidulans was freed from ammonium repression by l-methionine-d,l-sulfoximi ... | 1981 | 6780511 |
| plasmids from two morphologically distinct cyanobacterial strains share a novel replication origin. | a 2.9-kbp replication origin from a plasmid endogenous to the filamentous cyanobacterium fremyella diplosiphon utex 481 was genetically characterized and sequenced. deletion analysis of the 2.9-kbp dna fragment delimited the minimum region necessary for replication in f. diplosiphon fd33 to approximately 2.5 kbp. dna sequence analysis revealed that the f. diplosiphon plasmid replication origin is structurally very similar to and shares significant identity with the 1.75-kbp replication origin re ... | 1993 | 8366056 |
| general distribution of the nitrogen control gene ntca in cyanobacteria. | the ntca gene from synechococcus sp. strain pcc 7942 encodes a regulatory protein which is required for the expression of all of the genes known to be subject to repression by ammonium in that cyanobacterium. homologs to ntca have now been cloned by hybridization from the cyanobacteria synechocystis sp. strain pcc 6803 and anabaena sp. strain pcc 7120. sequence analysis has shown that these ntca genes would encode polypeptides strongly similar (77 to 79% identity) to the synechococcus ntca prote ... | 1993 | 8366058 |
| atp-dependent uptake of nitrate in nostoc muscorum and inhibition by ammonium ions. | a high rate of nitrate uptake was observed in nostoc muscorum when cells were grown on elemental nitrogen as compared to that when they were grown on nitrate or ammonium. the uptake of nitrate was light dependent. however, supplementation with atp (50 microm) stimulated nitrate uptake both in light and darkness. adp, under similar conditions had no effect. 3-(3,4-dichlorophenyl)-1,1-dimethylurea (dcmu), 2-n-heptyl-4-hydroxyquinoline, (hoqno) and kcn inhibited nitrate uptake in light which could ... | 1981 | 6786358 |
| characterization of a cta/cde operon-like genomic region encoding subunits i-iii of the cytochrome c oxidase of the cyanobacterium synechocystis pcc 6803. | strong heterologous hybridization of a synthetic oligonucleotide probe of 17 bp originally used to clone subunit i of the paracoccus denitrificans cytochrome c oxidase (m. raitio, t. jalli and m. saraste (1987) embo j. 6, 2825-2833) to a single band was observed on southern blots of anacystis nidulans r2 (synechococcus pcc 7942), synechocystis pcc 6803, and nostoc mac pcc 8002 chromosomal dna digests. six pooled gene banks prepared from synechocystis pcc 6803 contained regions that hybridized to ... | 1993 | 8387368 |
| characterization of genes for an alternative nitrogenase in the cyanobacterium anabaena variabilis. | anabaena variabilis atcc 29413 is a heterotrophic, nitrogen-fixing cyanobacterium that has been reported to fix nitrogen and reduce acetylene to ethane in the absence of molybdenum. dna from this strain hybridized well at low stringency to the nitrogenase 2 (vnfdgk) genes of azotobacter vinelandii. the hybridizing region was cloned from a lambda embl3 genomic library of a. variabilis, mapped, and sequenced. the deduced amino acid sequences of the vnfd and vnfk genes of a. variabilis showed only ... | 1993 | 8407800 |
| copper toxicity and phosphate utilization in the cyanobacterium nostoc calcicola. | | 1993 | 8422521 |
| 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. | a mutant of anabaena sp. strain pcc 7120, called pat-2, that grows poorly under nitrogen-fixing conditions, has been isolated. the heterocysts of the mutant strain develop much more slowly than those of the wild type and are spaced more closely in an older culture of the mutant than in the wild type. the wild-type gene that complements the mutation in pat-2, called patb, was isolated and characterized. the predicted 529-amino-acid patb protein contains a region very similar to the fe4s4 bacteria ... | 1993 | 8449877 |
| the rubisco activase (rca) gene is located downstream from rbcs in anabaena sp. strain ca and is detected in other anabaena/nostoc strains. | a gene encoding ribulose 1,5-bisphosphate carboxylase/oxygenase (rubisco) activase (rca) was found downstream from the rbclrbcs operon in the heterocystous cyanobacterium anabaena sp. strain ca. two unknown open reading frames were shown to be located between rbcs and rca in strain ca and all the genes, rbclrbcs, orf1, orf2, and rca were in the same transcriptional orientation. the deduced amino acid sequence of the anabaena rubisco activase showed both similarities and differences to the plant ... | 1993 | 8467074 |
| recovery of nostoc muscorum previously exposed to some triazine and phenylurea herbicides. | | 1993 | 8490271 |