| chromatic adaptation in a mutant of fremyella diplosiphon incapable of phycoerythrin synthesis. | a mutant of the chromatically adapting cyanobacterium fremyella diplosiphon, incapable of phycoerythrin synthesis but responding to wavelength modulation of its biliprotein content, was isolated. the biliprotein composition of the mutant and of the wild type were identical after growth in red light, but green light induced, in the mutant, the synthesis of a biliviolin-type chromophore bound to some of the alpha subunits of its phycocyanin. implications of the results on the regulation and possib ... | 1985 | 3922434 |
| microinjected photoreactivating enzymes from anacystis and saccharomyces monomerize dimers in chromatin of human cells. | photoreactivating enzymes (pre) from the yeast saccharomyces cerevisiae and the cyanobacterium anacystis nidulans have been injected into the cytoplasm of repair-proficient human fibroblasts in culture. after administration of photoreactivation light, pre-injected cells displayed a significantly lower level of uv-induced unscheduled dna synthesis (uds) than non-injected cells. this indicates that monomerization of the uv-induced pyrimidine dimers in the mammalian chromatin had occurred as a resu ... | 1985 | 3923332 |
| effects of environmental factors on toxicity of a cyanobacterium (microcystis aeruginosa) under culture conditions. | effects of light intensity, temperature, and nutrients on the toxicity of microcystis aeruginosa were investigated, using a toxic strain which kills mice. a marked change in toxicity was observed in the light intensity experiment, and slight changes were observed to be caused by temperature and phosphorus deficiency. | 1985 | 3923932 |
| interaction effects of mercury-pesticide combinations towards a cyanobacterium. | | 1985 | 3924147 |
| 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 |
| the primary structure of thioredoxin from the filamentous cyanobacterium anabaena sp. 7119. | thioredoxin from the cyanobacterium anabaena 7119 serves as electron donor to ribonucleotide reductase and as a protein disulfide reductase. this small, heat-stable protein was found to have structural and functional similarities to thioredoxins from both bacterial and mammalian sources. we here report the complete primary structure of anabaena thioredoxin. the structure was determined by analysis of peptides obtained after cleavage with cyanogen bromide, staphylococcus aureus protease, and tryp ... | 1985 | 3926769 |
| a firefly luciferase assay for determination of cytidine 5'-triphosphate in biological samples. | a routine assay for ctp in cell and tissue extracts using crude firefly lantern preparations is described. atp, gtp, and utp are removed by incubation of the samples with a mixture of 3-phosphoglycerate kinase, hexokinase, glucose-6-phosphate dehydrogenase, and udp-glucose pyrophosphorylase in the presence of adp. the method is sensitive (greater than 30 nm ctp), inexpensive, and reproducible. no chromatographic purification of the biological samples or of the firefly extract is necessary. corre ... | 1985 | 3927776 |
| x-ray crystallographic structure of the light-harvesting biliprotein c-phycocyanin from the thermophilic cyanobacterium mastigocladus laminosus and its resemblance to globin structures. | the structure of the biliprotein c-phycocyanin from the thermophilic cyanobacterium mastigocladus laminosus has been determined at 3 a resolution by x-ray diffraction methods. phases have been obtained by the multiple isomorphous replacement method. the electron density map could be improved by solvent flattening and has been interpreted in terms of the amino acid sequence. the protein consists of three identical (alpha-beta)-units which are arranged around a threefold symmetry axis to form a di ... | 1985 | 3928897 |
| expression and assembly of active cyanobacterial ribulose-1,5-bisphosphate carboxylase/oxygenase in escherichia coli containing stoichiometric amounts of large and small subunits. | the genes for the large and small subunits of ribulose-1,5-bisphosphate carboxylase/oxygenase from the cyanobacterium anacystis nidulans were subcloned into plasmid puc9. after induction, both genes were expressed in escherichia coli and the subunits were assembled into an active holoenzyme. the enzyme was purified from e. coli to high specific activity and was found to contain equimolar amounts of large and small subunits. the assembly of the hexadecameric ribulose bisphosphate carboxylase/oxyg ... | 1985 | 3929249 |
| organization of pigment proteins in the photosystem ii complex of the cyanobacterium anacystis nidulans r2. | two chlorophyll-protein complexes associated with photosystem ii (psii) of the cyanobacterium anacystis nidulans r2 have been detected. the larger of the two complexes, cpvi-1, contained a 71-kda and a 42-kda protein. the 71-kda protein was determined to be the anchor protein of the phycobilisomes (the light-harvesting complex of a. nidulans psii), since it was recognized by an antibody raised against a similar protein from another cyanobacterium. the second complex, cpvi-4, contained a previous ... | 1985 | 3931080 |
| cyanobacterial light-harvesting complex subunits encoded in two red light-induced transcripts. | the major light-harvesting complex in cyanobacteria and red algae, the phycobilisome, is composed of chromophoric and nonchromophoric polypeptides. two linked genes encoding major chromophoric components, the polypeptide subunits of phycocyanin, were isolated from the cyanobacterium fremyella diplosiphon. transcripts from this phycocyanin subunit gene cluster were present as major species in the cyanobacterium grown in red light, but not in cultures maintained in green light. the genes for the s ... | 1985 | 3931221 |
| desiccation resistance and contamination as mechanisms of gaia. | the gaia hypothesis, formulated by j.e. lovelock, asserts the composition of the reactive gases, the oxidation-reduction state and the temperature of the lower atmosphere of the planet earth are actively regulated by the biota. lovelock and watson, using highly simplified mathematical models, have shown that the modulation of atmospheric temperature can be achieved by exponentially growing populations of differently colored organisms ("dark and light daisies"). it is more likely that the modulat ... | 1985 | 3931720 |
| linker polypeptides of the phycobilisome from the cyanobacterium mastigocladus laminosus: amino-acid sequences and relationships. | three linker polypeptides of the phycobilisome from the cyanobacterium mastigocladus laminosus were isolated: a 8.9-kda polypeptide, l8.9r(c), which is probably associated with c-phycocyanin, a 34.5-kda polypeptide, l34.5,pcr, which forms a complex with c-phycocyanin, and a 34.5-kda polypeptide, l34.5,pecr, which is linked to phycoerythrocyanin. the complete amino-acid sequence (80 residues) of the l8.9r(c) polypeptide was determined as well as the n-terminal 44 residues of both l34.5r polypepti ... | 1985 | 3933528 |
| organization of the thylakoid membrane from the heterotrophic cyanobacterium, aphanocapsa 6714. | the polypeptide composition of thylakoid membrane fractions from the heterotrophic cyanobacterium aphanocapsa 6714 was examined by electrophoretic and immunoblotting procedures. we have identified thylakoid cytochromes f, b6, c-550 and c-553 by tetramethylbenzidine staining of lithium dodecyl sulfate polyacrylamide gels; we also have identified the rieske fe-s center protein and subunit 4 of the cytochrome b6/f complex. we have characterized phycobilisomes and active core preparations of ps i an ... | 1985 | 3933560 |
| 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 |
| the euglena gracilis chloroplast ribulose-1,5-bisphosphate carboxylase gene. ii. the spliced mrna and its product. | the polypeptide product of the gene for the large subunit of ribulose-1,5-bisphosphate carboxylase from euglena gracilis based on the dna sequence of the chloroplast-encoded gene is described. the large subunit polypeptide of 475 codons is co-linear with the homologous polypeptides from other chloroplasts and cyanobacteria. the amino acid sequence is 92% homologous to that of chlamydomonas, 84% homologous to spinach, 82% homologous to maize, and 80% homologous to that of the cyanobacterium anaba ... | 1985 | 3934171 |
| crystallization of phycoerythrocyanin from the cyanobacterium mastigocladus laminosus and preliminary characterization of two crystal forms. | the light-harvesting protein phycoerythrocyanin from the cyanobacterium mastigocladus laminosus cohn has been crystallized in two different crystal forms by vapour diffusion. in 5% (w/v) polyethylene glycol at ph 8.5, hexagonal crystals of space group p63 with cell constants a = b = 158 a, c = 40.6 a were obtained, which turned out to be almost isomorphous with the hexagonal crystals of c-phycocyanin from the same organism. consequently, the conformation of both phycobiliproteins must be very si ... | 1985 | 3935798 |
| comparison of amino acid sequences between phosphoenolpyruvate carboxylases from escherichia coli (allosteric) and anacystis nidulans (non-allosteric): identification of conserved and variable regions. | amino acid sequences of phosphoenolpyruvate carboxylases of escherichia coli (allosteric) and a cyanobacterium anacystis nidulans (non-allosteric) were aligned. the pattern of homology suggests that the enzyme molecule is comprised of two distinct regions, namely, a conserved region (c-terminal half) and a variable region (n-terminal half). among the amino acid residues which have previously been presumed essential for the catalytic activity, three histidine residues were found to be conserved, ... | 1985 | 3936496 |
| severe hepatotoxicity caused by the tropical cyanobacterium (blue-green alga) cylindrospermopsis raciborskii (woloszynska) seenaya and subba raju isolated from a domestic water supply reservoir. | cylindrospermopsis raciborskii, a tropical blooming species of cyanobacterium (blue-green alga), was isolated from the domestic water supply reservoir on palm island, a continental island off the tropical northeast coast of australia. this species, not previously known to be toxic, was shown to be severely hepatotoxic for mice. the 50% lethal dose at 24 h after injection was found to be 64 +/- 5 mg of freeze-dried culture per kg of mouse. the principal lesion produced was centrilobular to massiv ... | 1985 | 3937492 |
| the mutagenesis and temporal partial genetic mapping in the cyanobacterium spirulina platensis. | | 1985 | 3938946 |
| the action of n-methyl-n'-nitro-n-nitrosoguanidine (ntg) on the cyanobacterium plectonema boryanum. | | 1985 | 3938947 |
| cotranscription of genes encoding the small and large subunits of ribulose-1,5-bisphosphate carboxylase in the cyanobacterium anabaena 7120. | in the filamentous cyanobacterium anabaena, the gene for the small subunit (rbcs) of ribulose-1,5-bisphosphate carboxylase is linked to and transcribed together with the gene encoding the large subunit (rbcl) of the same enzyme. the two genes are separated by a spacer of 545 base pairs (bp) that does not contain an open reading frame. both genes hybridize with a predominant 3.1-kilobase transcript that initiates 414 bp upstream from the rbcl coding region. the nucleotide sequence 14-8 bp precedi ... | 1984 | 6091125 |
| 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 |
| proton movements and electric potential generation in reconstituted atpase proteoliposomes from the thermophilic cyanobacterium synechococcus 6716. | atp hydrolysis-induced proton translocation and electric potential generation have been studied in atpase proteoliposomes by means of various optical probes. the proteoliposomes consisted of reconstituted atpase complex and native lipid mixture isolated from the thermophilic cyanobacterium synechococcus 6716 [van walraven et al. (1983) eur. j. biochem. 137, 101-106]. the native cartenoids and added oxonol vi served as probes for the electric membrane potential generated by the net charge separat ... | 1984 | 6092075 |
| triton x-114 phase fractionation of membrane proteins of the cyanobacterium anacystis nidulans r2. | the thylakoid polypeptides of the cyanobacterium anacystis nidulans r2 were analyzed by triton x-114 phase fractionation [c. bordier (1981) j. biol. chem. 256, 1604-1607, as adapted for photosynthetic membranes by t.m. bricker and l.a. sherman (1982) febs lett. 149, 197-202]. in this procedure, polypeptides with extensive hydrophobic regions (i.e., intrinsic proteins) form mixed micelles with triton x-114, and are separated from extrinsic proteins by temperature-mediated precipitation of the mix ... | 1984 | 6093709 |
| isolation and characterization of thioredoxin f from the filamentous cyanobacterium, anabaena sp. 7119. | two thioredoxin fractions had previously been reported to occur in anabaena 7119 by buchanan and co-workers (yee, b. c., dela torre, a., crawford, n. a., lara, c., carlson, d. e., and buchanan, b. b. (1981) arch. microbiol. 130, 14-18). these proteins were detected by their ability to activate spinach fructose-1,6-bisphosphatase (fru-p2-ase). the partially purified proteins resembled similar thioredoxins found in spinach chloroplasts and were designated thioredoxin f (tf) for the fraction most e ... | 1984 | 6094540 |
| chloroplast promoter driven expression of the chloramphenicol acetyl transferase gene in a cyanobacterium. | the putative promoter region of the chloroplast encoded ps2b gene (the gene encoding the 32kd herbicide binding b protein of photosystem ii (1-4)) has been fused to a chloramphenicol acetyl transferase (cat) gene that lacks its bacterial promoter and found to accurately initiate transcription from this promoter when introduced into the cyanobacterium, anacystis nidulans r2 (or into e. coli). the chloroplast promoter-cat fusion was introduced into the cells on a plasmid that contains plasmid repl ... | 1984 | 6096812 |
| cloning of a third nitrate reductase gene from the cyanobacterium anacystis nidulans r2 using a shuttle cosmid library. | a strategy for gene cloning in the cyanobacterium anacystis nidulans r2 was developed which made use of a gene library constructed in a shuttle cosmid vector. the method involved phenotypic complementation of mutants with pooled cosmid dna. the development of the procedure and its application to the cloning of a third gene involved in nitrate reduction are described. | 1984 | 6098517 |
| enzymological basis for growth inhibition by l-phenylalanine in the cyanobacterium synechocystis sp. 29108. | the pattern of allosteric control in the biosynthetic pathway for aromatic amino acids provides a basis to explain vulnerability to growth inhibition by l-phenylalanine (0.2 mm or greater) in the unicellular cyanobacterium synechocystis sp. 29108. we attribute growth inhibition to the hypersensitivity of 3-deoxy-d-arabinoheptulosonate 7-phosphate synthase to feedback inhibition by l-phenylalanine. hyperregulation of this initial enzyme of aromatic biosynthesis depletes the supply of precursors n ... | 1980 | 6108316 |
| in vivo regulation of glutamine synthetase by ammonium in the cyanobacterium anabaena l-31. | | 1981 | 6111293 |
| regulatory isozymes of 3-deoxy-d-arabinoheptulosonate 7-phosphate synthase in the cyanobacterium anabaena sp. strain atcc 29151. | two regulatory isozymes of 3-deoxy-d-arabinoheptulosonate 7-phosphate synthase from the cyanobacterium anabaena sp. strain atcc 29151 were separated via gel filtration. one isozyme (mr = 205,000) was sensitive to phenylalanine inhibition, and the other (mr = 60,000) was sensitive to tyrosine inhibition. the tyrosine-sensitive isozyme from wild-type cells was unstable to gel filtration, whereas the corresponding isozyme from an analog-resistant mutant was insensitive to tyrosine inhibition and wa ... | 1981 | 6116697 |
| purification, physical characterization, and nh2-terminal sequence of glutamine synthetase from the cyanobacterium anabaena 7120. | a procedure for the complete purification of glutamine synthetase (l-glutamate:ammonia ligase (adp-forming), ec 6.3.1.2) from the cyanobacterium (blue-green alga) anabaena 7120 is described. the enzyme has structural characteristics in common with glutamine synthetases from other sources: a subunit molecular weight of approximately 50,000 and a native structure, determined by low dose exposure electron microscopy, consisting of a two-layered regular hexagon made up of 12 subunits. sequence analy ... | 1981 | 6118370 |
| kinetic and inhibition studies of glutamine synthetase from the cyanobacterium anabaena 7120. | a number of biochemical parameters of glutamine synthetase (ec 6.3.1.2) isolated from the cyanobacterium anabaena 7120 were determined. apparent michaelis constants for glutamate and atp were found to be 2.1 and 0.32 mm, respectively; that for ammonia was found to be below 20 microm, significantly lower than that reported for glutamine synthetases from other species. serine, alanine, glycine, cysteine, aspartic acid, methionine sulfone, and methionine sulfoximine were found to inhibit the enzyme ... | 1981 | 6118371 |
| regulation of glutamine synthetase activity and synthesis in free-living and symbiotic anabaena spp. | regulation of the synthesis and activity of glutamine synthetase (gs) in the cyanobacterium anabaena sp. strain 7120 was studied by determining gs transferase activity and gs antigen concentration under a variety of conditions. extracts prepared from cells growing exponentially on a medium supplemented with combined nitrogen had a gs activity of 17 mumol of gamma-glutamyl transferase activity per min per mg of protein at 37 degrees c. this activity doubled in 12 h after transfer of cells to a ni ... | 1982 | 6127334 |
| regulation of the aromatic pathway in the cyanobacterium synechococcus sp. strain pcc6301 (anacystis nidulans). | a pattern of allosteric control for aromatic biosynthesis in cyanobacteria relies upon early-pathway regulation as the major control point for the entire branched pathway. in synechococcus sp. strain pcc6301 (anacystis nidulans), two enzymes which form precursors for l-phenylalanine biosynthesis are subject to control by feedback inhibition. 3-deoxy-d-arabino-heptulosonate 7-phosphate synthase (first pathway enzyme) is feedback inhibited by l-tyrosine, whereas prephenate dehydratase (enzyme step ... | 1983 | 6129240 |
| evidence for ammonia as an inhibitor of heterocyst and nitrogenase formation in the cyanobacterium anabaena cycadeae. | growth and regulation of heterocyst and nitrogenase by fixed nitrogen sources were studied comparatively in parent and glutamine auxotrophic mutant of anabaena cycadeae. the parent strain grew well on n2, nh+4 or glutamine while the mutant strain grew on glutamine but not on n2 or nh+4. the total lack of active glutamine synthetase in the mutant strain thus appears to be the reason for its observed lack of growth in n2 or nh+4, which explains why it is a glutamine auxotroph and at the same time ... | 1983 | 6131672 |
| primary structure of the peptidoglycan from the unicellular cyanobacterium synechocystis sp. strain pcc 6714. | a peptidoglycan fraction free of non-peptidoglycan components was isolated from the unicellular cyanobacterium synechocystis sp. strain pcc 6714. hydrofluoric acid treatment (48%, 0 degrees c, 48 h) cleaved off from the peptidoglycan non-peptidoglycan glucosamine, mannosamine, and mannose. the purified peptidoglycan consists of n-acetyl muramic acid, n-acetyl glucosamine, l-alanine, d-alanine, d-glutamic acid, and meso-diaminopimelic acid in approximately equimolar amounts. at least partial amid ... | 1983 | 6131881 |
| the role of specific cations in regulation of cyanobacterial glutamine synthetase. | purified glutamine synthetase from the cyanobacterium anabaena cylindrica required a divalent cation for activity. maximum biosynthetic activity required mg2+ (25 mm when supplied alone). co2+ and mn2+ each supported up to 20% of this activity; 12 other cations tested were ineffective. at 2.5 - 10 mm mg2+, 0.1 mm co2+ or ethylene glycol-bis-(beta-aminoethyl ether) n,n'-tetraacetic acid (egta) stimulated gs activity to maximum rates; other divalent cations (particularly mn2+) inhibited mg2+-depen ... | 1983 | 6136275 |
| glutamine and glutamate transport by anabaena variabilis. | anabaena variabilis, a dinitrogen-fixing cyanobacterium, has high- and low-affinity systems for the transport of glutamine and glutamate. the high-affinity systems have km values of 13.8 and 100 microm and maximal rates of 13.2 and 14.4 nmol x min-1 x mg of chlorophyll a-1 for glutamine and glutamate, respectively. the low-affinity systems have km values of 1.1 and 1.4 mm and maximal rates of 125 and 100 nmol x min-1 x mg of chlorophyll a-1 for glutamine and glutamate, respectively. glutamine wa ... | 1983 | 6137473 |
| purification and characterization of thioredoxin from the n2-fixing cyanobacterium anabaena cylindrica. | thioredoxin has been purified to homogeneity from the cyanobacterium anabaena cylindrica. the protein consists of a single polypeptide chain with a relative molecular mass of about 11 680 which has two cysteine residues (residues 31 and 34) in the sequence-cys-gly-pro-cys- and an isoelectric point at ph 4.55. the n-terminal amino acid sequence of 39 residues shows distinct homologies with the sequences of escherichia coli and corynebacterium nephridii thioredoxins. anti-(a. cylindrica thioredoxi ... | 1984 | 6146520 |
| the dna, rna and protein composition of the cyanobacterium anacystis nidulans grown in light- and carbon dioxide-limited chemostats. | the dna, rna and protein content of the cyanobacterium anacystis nidudlans was determined in light-limited and carbon dioxide-limited chemostat cultures over the dilution rate range, d = 0.02 h-1 to 0.19 h-1. the macromolecular contents as a percentage of the dry weight and on a per cell basis varied significantly as a function of organism growth rate and the nature of the growth conditions. for both limitations the rna content per cell increased [20-55 fg rna (cell)-1] with increasing dilution ... | 1980 | 6158924 |
| characterization of reconstituted atpase complex proteoliposomes prepared from the thermophilic cyanobacterium synechococcus 6716. | the preparation and some properties are described of proteoliposomes consisting of the atpase complex and lipids from the thermophilic cyanobacterium synechococcus 6716. in the proteoliposomes (about 200 nm in diameter) only a low amount of protein can be incorporated (protein/lipid ratio of 0.01 w/w) and they show very few protein particles on freeze-fracture replicas. the octyl glucoside and cholate dialysis method of reconstitution yielded stable proteoliposomes with a relatively low proton p ... | 1983 | 6197302 |
| isolation, purification and characterization of the atpase complex from the thermophilic cyanobacterium synechococcus 6716. | the atpase complex is isolated and purified from membrane vesicles of the thermophilic cyanobacterium synechococcus 6716 by octyl glucoside and cholic acid by a modification of the procedure for its extraction from spinach chloroplasts. the complex is purified by differential centrifugation and ammonium sulfate precipitation and by gel filtration on sepharose 6b. the purified fraction, without any phycocyanin contamination, shows atp hydrolysis activity and pi/atp exchange activity of 1564 and 3 ... | 1983 | 6197306 |
| heterocyst differentiation in cylindrospermum licheniforme: studies on the role of transcription. | heterocysts of the cyanobacterium cylindrospermum licheniforme occur at the ends of the filaments. these cells, specialized for aerobic n2 fixation, synchronously differentiate after the fragmentation of filaments grown in a medium free of combined nitrogen. this study has examined the role of transcription during and after heterocyst differentiation. autoradiography of intact filaments pre-labelled for 3 h with [3h]uracil revealed that rna synthesis occurred at similar rates in vegetative cells ... | 1984 | 6204007 |
| a new method for identification of heterocysts and proheterocysts in morphologically complex cyanobacteria. | a new light microscopic method for identifying heterocysts and proheterocysts in morphologically complex cyanobacteria was evaluated for reliability and usefulness. mature heterocysts and proheterocysts could be distinguished readily from vegetative cells in 0.25 micron sections of fixed and embedded material after staining with toluidine blue. examination by light and electron microscopy of the same specimens indicated that the staining reactions which served to differentiate these cell types w ... | 1984 | 6207642 |
| purification of a high molecular weight membrane protein by fast protein liquid chromatography: the atpase complex of a thermophilic cyanobacterium. | fast protein liquid chromatography (fplc) with a strong anion-exchange (mono q) column is applied to the purification of a high molecular weight membrane protein. the atpase complex of the thermophilic cyanobacterium synechococcus 6716, partially purified by ammonium sulfate precipitation, was fractionated in the presence of the detergent octylglucoside. the atpase complex containing fractions were eluted by a linear nacl gradient at about 0.4 m and within 10 min. the fplc fractions were analyze ... | 1984 | 6234347 |
| lipid specificity for the reconstitution of well-coupled atpase proteoliposomes and a new method for lipid isolation from photosynthetic membranes. | the lipid specificity for the enzymatic and proton-translocating functions of a reconstituted thermophilic atpase complex has been investigated. the proteoliposomes were prepared from the atpase complex of the thermophilic cyanobacterium synechococcus 6716 and various lipids and lipid mixtures extracted from this organism and from a related mesophilic strain. some commercial lipids were used as well. an improved method of lipid extraction from chlorophyll-containing membranes is presented. this ... | 1984 | 6237908 |
| a new sequence-specific endonuclease from a thermophilic cyanobacterium, mastigocladus laminosus. | | 1980 | 6244195 |
| occurrence of cytochrome aa3 in anacystis nidulans. | the cytochrome content of membrane fragments prepared from the blue-green alga (cyanobacterium) anacystis nidulans was examined by difference spectrophotometry. two beta-type cytochromes and hitherto unknown cytochrome alpha could be characterized. in the reduced-minus-oxidised difference spectra the alpha-type cytochrome showed an alpha-band at 605 nm and a gamma-band at 445 nm. these bands shifted to 590 and 430 nm, respectively, in co difference spectra, nadph, nadh and ascorbate reduced the ... | 1981 | 6263333 |
| mössbauer spectroscopic studies of the nature of centre x of photosystem i reaction centres from the cyanobacterium chlorogloea fritschii. | reduced photosystem i samples, which give the electron paramagnetic resonance (epr) signals associated with a, a and b, and a, b and x centres, have been studied using mössbauer spectroscopy. the mössbauer spectra obtained from each type of sample is different, which indicates that iron is associated with all three centres. the spectra are similar to those obtained from ferredoxins with 4fe-4s centres and were fitted with oxidized and reduced components, the relative proportions depending on the ... | 1981 | 6269849 |
| vectors for cloning in cyanobacteria: construction and characterization of two recombinant plasmids capable of transformation of escherichia coli k12 and anacystis nidulans r2. | two plasmids were constructed consisting of the e. coli vector pacyc184 and the cyanobacterial plasmid puc1. these recombinants, designated puc104 and puc105, can be transformed to e. coli k12 as well as to the cyanobacterium anacystis nidulans r2 and in both hosts they express their antibiotic markers. puc104 and puc105 differ with respect to the location and the orientation of the pacyc184 segment in puc1. puc104 was found to be stable under all circumstances. transformation of puc105 to a. ni ... | 1981 | 6276694 |
| construction of a hybrid plasmid capable of replication in the bacterium escherichia coli and the cyanobacterium anacystis nidulans. | a hybrid plasmid was constructed between the 5.3-megadalton plasmid (puh24) of anacystis nidulans r2 and the escherichia coli plasmid pbr322. this was accomplished by adding a transposon to pbr322 and transforming this dna into a. nidulans. one resultant hybrid, pls103, had a molecular weight of 6.8 x 10(6), replicated in both organisms, had unique sites for two restriction endonucleases, conferred ampicillin resistance on both organisms, and could be used as a cloning vector in a. nidulans. | 1982 | 6277870 |
| regulatory properties of a fructose 1,6-bisphosphatase from the cyanobacterium anacystis nidulans. | a fructose 1,6-bisphosphatase (ec 3.1.3.11) (fbpase) was purified over 100-fold from anacystis nidulans. at variance with a previous report (r. h. bishop, arch. biochem. biophys. 196:295-300, 1979), the regulatory properties of the enzyme were found to be like those of chloroplast enzymes rather than intermediate between chloroplast (photosynthetic) and heterotrophic fbpases. the ph optimum of anacystis fbpase was between 8.0 and 8.5 and shifted to lower values with increasing mg2+ concentration ... | 1982 | 6282804 |
| a physical map of plasmid pdu1 from the cyanobacterium nostoc pcc 7524. | | 1982 | 6283572 |
| isolation and physical mapping of nitrogen fixation genes from the cyanobacterium anabaena 7120. | | 1982 | 6290496 |
| proton pump coupled to cytochrome c oxidase in the cyanobacterium anacystis nidulans. | intact spheroplasts of the cyanobacterium anacystis nidulans were found to oxidize various exogenous c-type cytochromes with concomitant proton extrusion. in the coupled state, h+/e stoichiometries close to 1 were measured, regardless of absolute reaction rates. it is concluded that the proton translocation observed is an intrinsic property of the cytoplasmic membrane-bound cytochrome c oxidase of a. nidulans. | 1983 | 6294060 |
| 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 new approach for molecular cloning in cyanobacteria: cloning of an anacystis nidulans met gene using a tn901-induced mutant. | a new strategy for molecular cloning in the cyanobacterium anacystis nidulans r-2 is described. this strategy involved the use of a transposon and was developed for the cloning of a gene encoding methionine biosynthesis. a met::tn901 mutant was isolated. chromosomal dna fragments were cloned in the escherichia coli plasmid vector pacyc184. a recombinant plasmid carrying the inactivated met::tn901 gene was selected after transformation to e. coli. the cloned met::tn901 dna fragment was used as a ... | 1982 | 6298064 |
| unusual sulfonolipids are characteristic of the cytophaga-flexibacter group. | capnocytophaga spp. contain a group of unusual sulfonolipids, called capnoids (w. godchaux iii and e. r. leadbetter, j. bacteriol. 144:592-602, 1980). one of these lipids, capnine, is 2-amino-3-hydroxy-15-methylhexadecane-1-sulfonic acid; the others are, apparently, n-acylated versions of capnine. the lipids were found, in amounts ranging from 2.5 to 16 mumol of capnoid sulfur per g of cells (wet weight), in two cytophaga spp. and also in several closely related organisms: several capnocytophaga ... | 1983 | 6298180 |
| the structural nif genes of the cyanobacteria gloeothece sp. and calothrix sp. share homology with those of anabaena sp., but the gloeothece genes have a different arrangement. | probes carrying the anabaena sp. strain pcc 7120 nitrogenase reductase (nifh) and nitrogenase (nifk and nifd) genes were hybridized to southern blots of dna from the unicellular, aerobic nitrogen-fixing cyanobacterium gloeothece sp. strain pcc 6909 and from the filamentous cyanobacterium calothrix sp. strain pcc 7601. these data suggest that the gloeothece sp. nif structural proteins must be similar to those of other diazotrophs and that the ability for aerobic nitrogen fixation does not reside ... | 1983 | 6305921 |
| flash spectroscopic characterization of photosynthetic electron transport in isolated heterocysts. | electron transport was studied in heterocysts of the filamentous cyanobacterium anabaena 7120 using spectral and kinetic analysis of absorbance transients elicited by single turnover flashes. consistent photosynthetic turnovers were observed only in the presence of an exogenous source of reductant; therefore measurements were routinely made under a gas phase containing h2. prominent absorbance changes corresponding to the oxidation of cytochrome c (554 nm) and the reduction of cytochrome b563 (5 ... | 1983 | 6307149 |
| the nucleotide sequence for the large subunit of ribulose 1,5-bisphosphate carboxylase from a unicellular cyanobacterium, synechococcus pcc6301. | the gene for the large subunit (lsu) of ribulose 1,5-bisphosphate carboxylase from a unicellular cyanobacterium, synechococcus pcc6301, was cloned using the spinach lsu gene as a hybridization probe. the coding region of the synechococcus lsu gene consists of 1419 nucleotides and shows 70% homology to the spinach nucleotide sequence. the derived amino acid sequence (472 amino acids) shows 81% homology to the spinach lsu and 78% to the maize lsu. regions containing active-site residues are highly ... | 1983 | 6307620 |
| utilization of energy stored in the form of na+ and k+ ion gradients by bacterial cells. | the hypothesis that na+ and k+ gradients have an energy storing function [v. p. skulachev (1978) febs lett. 87, 171-176] has been tested in experiments with escherichia coli, the marine bacterium vibrio harveyi, an extremely halophilic halobacterium halobium and a fresh-water cyanobacterium phormidium uncinatum from lake baikal living at an extremely low salt concentration. the capability of these microorganisms to maintain delta microh was compared using motility as a delta microh-supported fun ... | 1983 | 6307692 |
| a new hybrid plasmid capable of transforming escherichia coli and anacystis nidulans. | we have constructed a hybrid plasmid, pdf30, by combining the 8-kb pdf3 plasmid derived from the cyanobacterium anacystis nidulans 6311 with the escherichia coli vector pbr325. pdf30 transforms, replicates and confers chloramphenicol resistance (cmr) and ampicillin resistance (apr) on both a. nidulans and e. coli. the level of resistance to ampicillin in a. nidulans transformants, although low, is above background resistance and an apr activity was demonstrated in cell-free extracts of a. nidula ... | 1983 | 6307827 |
| a hybrid plasmid is a stable cloning vector for the cyanobacterium anacystis nidulans r2. | anacystis nidulans r2 is a highly transformable strain which is suitable as a recipient for molecular cloning in cyanobacteria. in an effort to produce an appropriate cloning vector, we constructed a hybrid plasmid molecule, psg111, which contained pbr328 from escherichia coli and the native puh24 plasmid of a. nidulans. psg111 replicated in and conferred ampicillin and chloramphenicol resistance to both hosts. it contained unique sites for the restriction enzymes ecori, sali, sphi, and xhoi, wh ... | 1983 | 6309751 |
| shuttle cloning vectors for the cyanobacterium anacystis nidulans. | hybrid plasmids capable of acting as shuttle cloning vectors in escherichia coli and the cyanobacterium anacystis nidulans r2 were constructed by in vitro ligation. dna from the small endogenous plasmid of a. nidulans was combined with two e. coli vectors, pbr325 and pdpl13, to create vectors containing either two selectable antibiotic resistance markers or a single marker linked to a flexible multisite polylinker. nonessential dna was deleted from the polylinker containing plasmid pplan b2 to p ... | 1983 | 6311795 |
| a host-vector system for gene cloning in the cyanobacterium anacystis nidulans r2. | we describe the construction of a series of vectors suitable for gene cloning in the cyanobacterium anacystis nidulans r2. from the indigenous plasmid puh24, derivatives were constructed with streptomycin as the selective marker; one of these plasmids was used to construct puc303, a shuttle vector capable of replication in a. nidulans r2 as well as in escherichia coli k12. it has two markers, streptomycin and chloramphenicol resistance, and three unique restriction sites. instability of recombin ... | 1983 | 6314409 |
| 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 |
| complete nucleotide sequence of the 23s rrna gene of the cyanobacterium, anacystis nidulans. | the nucleotide sequence of the anacystis nidulans 23s rrna gene, including the 5'- and 3'-flanking regions has been determined. the gene is 2876 nucleotides long and shows higher primary sequence homology to the 23s rrnas of plastids (84.5%) than to that of e. coli (79%). the predicted rrna transcript also shares many secondary structural features with those of plastids, reinforcing the endosymbiont hypothesis for the origin of these organelles. | 1984 | 6326060 |
| cloning of nitrate reductase genes from the cyanobacterium anacystis nidulans. | anacystis nidulans, a non-nitrogen-fixing cyanobacterium, can fulfill its nitrogen requirement by the assimilation of nitrate. the first step in the pathway, the reduction of nitrate to nitrite, is catalyzed by the molybdo-protein nitrate reductase. in this study, newly developed techniques for gene cloning in a. nidulans r2 were used for the isolation of two genes involved in nitrate reduction. one gene was cloned by complementation of the corresponding mutant; the other gene was picked up from ... | 1984 | 6330039 |
| two tuf genes in the cyanobacterium spirulina platensis. | probes derived from the tufa gene of escherichia coli have been utilized to detect homologous sequences on spirulina platensis dna. a 6-kilobase-pair fragment of s. platensis dna appears to contain two sequences homologous to the e. coli gene. thus, as reported for gram-negative bacteria, the cyanobacterium presumably contains two tuf genes. | 1984 | 6330044 |
| mutations affecting chromatic adaptation in the cyanobacterium fremyella diplosiphon. | the chromatically adapting cyanobacterium, fremyella diplosiphon, when grown in cool white fluorescent light, contains phycoerythrin as its predominant phycobiliprotein. when grown on agar plates with cool white illumination, mutant colonies deficient or devoid of phycoerythrin can be visibly distinguished from the wild type. a total of 25 anomalously pigmented strains were isolated and examined for their ability to chromatically adapt. based on absorption spectra of cell extracts and on fluores ... | 1983 | 6402499 |
| chlorophyll-protein organization of membranes from the cyanobacterium anacystis nidulans. | six chlorophyll-containing bands were observed upon electrophoretic analysis of anacystis nidulans thylakoid membranes. these ranged in apparent molecular weights from approximately 360 to 45 kdalton. measurements of the light absorption and chlorophyll fluorescence properties of these bands revealed numerous differences among the aggregates. the larger chlorophyll-protein complexes had a chlorophyll absorption maximum at 676 nm while the smallest band, band vi, at approximately 45 kdalton, abso ... | 1983 | 6402983 |
| adenine nucleotide levels in and nitrogen fixation by the cyanobacterium anabaena sp. strain 7120. | adenine nucleotide levels were determined in whole filaments of anabaena sp. 7120 grown under different n2-fixing or non-n2-fixing conditions. these were compared with levels in isolated heterocysts, rhodospirillum rubrum, and azotobacter vinelandii. adenine nucleotides in whole filaments of anabaena sp. do not reflect the energetic expense of n2 fixation as they do in r. rubrum and a. vinelandii. however, adenine nucleotide levels in heterocysts were similar to the levels found in n2-fixing r. ... | 1983 | 6403506 |
| the cytochrome f-b electron-transport complex. a common link between photosynthesis and respiration in the cyanobacterium anacystis nidulans. | reduced-minus-oxidized difference spectra were recorded on particle preparations of the cyanobacterium anacystis nidulans. physiological oxidation of anaerobic membranes was effected either by o2 or by light. in both cases the spectral changes observed in the 550-570nm region were essentially the same. the results were confirmed by dual-wavelength spectrophotometry. it is concluded that a membrane-bound cytochrome f-b complex participates in both respiratory and photosynthetic elevtron transport ... | 1983 | 6405742 |
| structure of oxidized flavodoxin from anacystis nidulans. | the structure of oxidized flavodoxin from the cyanobacterium anacystis nidulans has been determined at 2.5 a resolution with phases calculated from ethylmercury phosphate and dimercuriacetate derivatives. the determination of partial sequences, including a total of 85 residues, has assisted in the interpretation of the electron density. preliminary refinement of a partial model (1072 atoms) has reduced r to 0.349 for the 10.997 reflections between 2.0 and 5.0 a with 1 greater than 2 sigma. the p ... | 1983 | 6406674 |
| atypical pulmonary thrombosis caused by a toxic cyanobacterial peptide. | parenteral injection into mice of a toxic pentapeptide isolated from the cyanobacterium microcystis aeruginosa induced thrombocytopenia, pulmonary thrombi, and hepatic congestion. the lethality of the toxin was unaffected by several anticoagulants. the acute liver damage that follows injection of the toxin has been attributed to direct action on liver cells but may be due to hypoxemia, heart failure, and shock. | 1983 | 6407109 |
| a requirement for ca2+ in the extraction of o2-evolving photosystem 2 preparations from the cyanobacterium anacystis nidulans. | ca2+ has been shown to be essential for the retention of maximal o2-evolving activity in photosystem 2 particles extracted by using dodecyldimethylamine oxide from anacystis nidulans thylakoids. the effect cannot entirely be mimicked by using mg2+. ca2+ stimulates electron transport from diphenylcarbazide to 2,6-dichloroindophenol catalysed by lead-inhibited cation-free preparations, showing the presence of two cation-binding sites in these particles. photosystem 2 preparations extracted in ca2+ ... | 1983 | 6407476 |
| regulation of hydrogenase activity in vegetative cells of anabaena variabilis. | heterocyst-free (nh4+-grown) cultures of the cyanobacterium anabaena variabilis produce a hydrogenase which is reversibly inhibited by light and o2. white or red light at an intensity of 5,000 lx inhibited greater than 95% of the activity. oxygen at concentrations as low as 0.5% inhibited more than 85% of the hydrogenase in the vegetative cells of co2-nh4+-grown cultures. the vegatative cell hydrogenase is also sensitive to strong oxidants like ferricyanide. in the presence of strong reductants ... | 1983 | 6408057 |
| drift in ultraviolet sensitivity and expression of mutations during synchronous growth of cyanobacterium anacystis nidulans. | synchrony with respect to cell division and dna synthesis in cultures of anacystis nidulans was induced by a light-dark-light regimen. at periodic intervals in the cell-division cycle, dna, rna, protein contents, uv sensitivity and induction of mutations were assayed. the dna, rna and protein syntheses were periodic and reached maximal values before the separation of cells. the dna content started to increase at about the 5th hour and doubled at about the 13th hour followed by a plateau of 4-6 h ... | 1983 | 6408466 |
| molecular weight of gas-vesicle protein from the planktonic cyanobacterium anabaena flos-aquae and implications for structure of the vesicle. | the gas vesicle of the planktonic cyanobacterium anabaena flos-aquae is a cylindrical shell made of protein enclosing a gas-filled space. protein sequence analysis shows that the vesicle is made from a single protein. by gel electrophoresis and amino acid analysis its molecular weight was estimated to be 20 600. taken with previously obtained x-ray data, a simple interpretation of its molecular structure is of the polypeptide snaking in six pairs of antiparallel chains, three in each layer. the ... | 1983 | 6409075 |
| the effects of acetaldehyde on nitrogenase, hydrogenase and photosynthesis in the cyanobacterium anabaena cylindrica. | acetaldehyde was shown to be an irreversible inhibitor of nitrogenase, hydrogenase, co2 fixation and growth in the cyanobacterium anabaena cylindrica, but had no effect on photosynthetic electron flow as measured by methyl viologen-dependent o2 uptake. the concentration-dependence of the inhibition of nitrogenase and hydrogenase activities was determined, and it was shown that acetaldehyde inhibition poses problems for anaerobic experiments in which the activities of these enzymes are measured i ... | 1983 | 6411074 |
| the complete amino-acid sequence of both subunits of phycoerythrocyanin from the thermophilic cyanobacterium mastigocladus laminosus. | the amino-acid sequences of both subunits of phycoerythrocyanin from the thermophilic cyanobacterium mastigocladus laminosus have been determined. the alpha-subunit consists of 162 amino-acid residues and has a molecular mass of 18200 da. the beta-subunit is 171 residues long and has a molecular mass of 19600 da. the tetrapyrrole chromophores are bound at position 84 in the alpha- and beta-subunits and at position 155 in the beta-subunit. the homology between the two subunits is 21%. the homolog ... | 1983 | 6411579 |
| three-dimensional ultrastructure of a unicellular cyanobacterium. | the first complete three-dimensional ultrastructural reconstruction of a cyanobacterium was accomplished with high-voltage electron microscopy and computer-aided assembly of serial sections. the precise arrangement of subcellular features within the cell body was very consistent from one cell to another. specialized inclusion bodies always occupied specific intracellular locations. the photosynthetic thylakoid membranes entirely surrounded the central portion of the cytoplasm, thereby compartmen ... | 1983 | 6411738 |
| transformation in the cyanobacterium synechococcus r2: improvement of efficiency; role of the puh24 plasmid. | systematic studies of the parameters influencing transformation efficiencies in synechococcus r2 and its spontaneous puh24 plasmid-minus variant s60, have led to substantial increases in these frequencies (up to 70 times for r2 and 9 times for s60) compared to those obtained by using previously published procedures. important factors are the physiological state of the host cells (competence occurs at the transition from first to second exponential phases of growth) and the conditions of expressi ... | 1983 | 6412037 |
| 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 |
| effect of iron deficiency and iron restoration on ultrastructure of anacystis nidulans. | the effects of iron deficiency and iron reconstitution on the ultrastructure of the unicellular cyanobacterium anacystis nidulans r2 were studied by electron microscopy. low-iron cells, grown with different amounts of aeration, were analyzed at 6, 12, and 24 h after the addition of iron. low-iron cells had a decrease in the quantities of membranes, phycobilisomes, and carboxysomes and a large increase in glycogen storage granules. in cells aerated with gentle shaking, the addition of iron caused ... | 1983 | 6413495 |
| ribulose 1,5-bisphosphate carboxylase from the halophilic cyanobacterium aphanothece halophytica. | various structural and functional properties of ribulose 1,5-bisphosphate carboxylase/oxygenase (rubisco) isolated from the halophilic cyanobacterium (blue-green alga) aphanothece halophytica were reexamined. the ready dissociation of this algal rubisco during sedimentation in a linear sucrose density gradient was observed. low nacl concentrations promote the dissociation of small subunit (b) from the original native enzyme molecule as evidenced by the sucrose density gradient centrifugation and ... | 1983 | 6414378 |
| two chlorophyll-binding subunits of the photosystem 2 reaction center complex isolated from the thermophilic cyanobacterium synechococcus sp. | the reaction center of photosystem 2 has been highly purified from digitonin-solubilized thylakoid membranes of the thermophilic cyanobacterium synechococcus sp. by means of sucrose density gradient centrifugation and electrophoresis on polyacrylamide gels containing digitonin. sodium dodecyl sulfate-polyacrylamide gel electrophoresis of isolated reaction center complex yielded four chlorophyll a proteins named cp2-a, cp2-b, cp2-c, and cp2-d. when reelectrophoresed, cp2-a was transformed to cp2- ... | 1983 | 6414380 |
| purification of the elongation factor tu (ef-tu) from the cyanobacterium spirulina platensis. | elongation factor tu (ef-tu) has been purified from the cyanobacterium spirulina platensis. by gel electrophoresis the mr of the purified protein appears to be 49 000, a value close to that reported for the ef-tu isolated from a number of bacteria but higher than that reported for the protein isolated from escherichia coli (43 000). functionally, however, s. platensis ef-tu may replace the e. coli protein in a protein-synthesizing system in vitro. in addition, its activity is affected by kirromy ... | 1983 | 6414811 |
| stable integration of foreign dna into the chromosome of the cyanobacterium synechococcus r2. | the blue-green alga, synechococcus r2, is transformed to antibiotic resistance by chimeric dna molecules consisting of synechococcus r2 chromosomal dna linked to antibiotic-resistance genes from escherichia coli. chimeric dna integrates into the synechococcus r2 chromosome by homologous recombination. the efficiency of transformation, as well as the stability of integrated foreign dna, depends on the position of the foreign genes relative to synechococcus r2 dna in the chimeric molecule. when th ... | 1983 | 6414889 |
| 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 |
| the gene for the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase is located close to the gene for the large subunit in the cyanobacterium anacystis nidulans 6301. | the gene for the small subunit (ss) of ribulose-1,5-bisphosphate carboxylase/oxygenase from a cyanobacterium, anacystis nidulans 6301, has been cloned and subjected to sequence analysis. the ss coding region is located close to and downstream from the large subunit (ls) coding region on the same dna strand. the spacer region between the ls and the ss coding regions contains 93 base pairs (bp), and has no promoter-like sequences. the coding region of a. nidulans ss gene contains 333 bp (111 codon ... | 1983 | 6415615 |
| the cyanobacteriales: a legitimate order based on the type strain cyanobacterium stanieri? | as a logical consequence of the definition of a bacterium (stanier and van niel, 1962), r. y. stanier created the name "cyanobacteria" as a replacement for "blue-green algae". as such, cyanobacteria entered the 8th issue of bergey's manual of determinative bacteriology 1974 as members of the procaryotae murray 1968, this kingdom being composed of two divisions, cyanobacteria and bacteria. an even tighter integration of cyanobacteria with other bacteria was proposed by gibbons and murray (1978) f ... | 1983 | 6416126 |
| lipopolysaccharides of the cyanobacterium microcystis aeruginosa. | lipopolysaccharides (lps) of two isolates of microcystis aeruginosa were extracted with phenol/water and purified. cesium chloride gradient ultracentrifugation of these preparations yielded only one fraction. the lps contained significant amounts of 3-deoxy-d-manno-octulosonic acid, glucose, 3-deoxy sugars, glucosamine, fatty acids, fatty acid esters, hexoses, and phosphate. heptose, a characteristic sugar component of the polysaccharide moiety of lps of most gram-negative bacteria was absent. l ... | 1983 | 6418544 |
| heterocyst differentiation in the cyanobacterium mastigocladus laminosus. | the morphological and ultrastructural aspects of heterocyst differentiation in the branching, filamentous cyanobacterium mastigocladus laminosus were examined with light and electron microscopy. the earliest differentiation stages involved cytoplasmic changes, including (i) rapid degradation of carboxysomes, (ii) degradation of polysaccharide granules, and (iii) accumulation of electron-dense ribosomal or protein material (or both). intermediate differentiation stages involved synthesis of a hom ... | 1984 | 6420391 |
| interaction of constituent subunits in ribulose 1,5-bisphosphate carboxylase from aphanothece halophytica. | ribulose 1,5-bisphosphate carboxylase-oxygenase (rubisco) from the halophilic cyanobacterium, aphanothece halophytica, dissociates into catalytic core (large subunit a oligomer) and small subunit b under low ionic strength during sucrose density gradient centrifugation. supplementation of kcl, nacl, or k2so4 ( [i] = 0.3 m) partly prevents the dissociation, the preventive effect of divalent cation salts such as mgcl2 and cacl2 being more effective than monovalent cation salts. rubisco with its hi ... | 1984 | 6422849 |
| the effect of suspended particulate material on cyanobacteria--cyanophage interactions in liquid culture. | the effect of the lytic phage lpp-dun1 on the cyanobacterium plectonema boryanum has been investigated in batch and in continuous cultures in the presence and absence of silt. in batch culture plectonema without added phage grew normally; the presence of phage caused rapid lysis of the cyanobacterium and the addition of silt prevented lysis by the phage. in continuous culture the numbers of cyanobacterial cells and phage particles oscillated in a reciprocal manner, but the addition of silt dampe ... | 1984 | 6423604 |
| purification and properties of glutathione reductase from the cyanobacterium anabaena sp. strain 7119. | an nadph-glutathione reductase (ec 1.6.4.2) has been purified 6,000-fold to electrophoretic homogeneity from the filamentous cyanobacterium anabaena sp. strain 7119. the purified enzyme exhibits a specific activity of 249 u/mg and is characterized by being a dimeric flavin adenine dinucleotide-containing protein with a ratio of absorbance at 280 nm to absorbance at 462 nm of 5.8, a native molecular weight of 104,000, a stokes radius of 4.13 nm, and a pi of 4.02. the enzyme activity is inhibited ... | 1984 | 6425264 |