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energy transduction in the photosynthetic membranes of the cyanobacterium (blue-green alga) p-lectonema boryanum.membrane preparations isolated from the photosynthetic lamellae of the cyanobacterium plectonema boryanum generate upon illumination a transmembrane ph gradient of approximately 2 to 3 ph units (acid inside), as determined from the distribution of either fluorescent or radioactive amines (9 aminoacridine and 14cmethylamine, respectively). using the distribution of permeant ions to measure the electrical potential across the membrane, it was found that the latter is practically nil under conditi ...197825283
phosphate metabolism in blue-green bacteria. v. factors affecting phosphate uptake in plectonema boryanum.plectonema boryanum requires approximately 5 days of exposure to a culture medium lacking phosphorus to induce the "polyphosphate overplus" phenomenon. at ph9, phosphate uptake is greatest both from normal culture medium and from dilute salt solutions. phosphate uptake from dilute salt solutions was greatest when na+ or k+ are combined with ca2+ or ca2+ and mg2+. cells starved of phosphorus in the presence of a high concentration of k+ or ca2+ in the medium, and then allowed to take up phosphoru ...197825703
phosphate metabolism in blue-green algae. iii. the effect of fixation and post-staining on the morphology of polyphosphate bodies in plectonema boryanum. 197770323
molybdenum independence of nitrogenase component synthesis in the non-heterocystous cyanobacterium plectonema.the cyanobacterium plectonema boryanum (iu 594-utex 594) fixes n2 only in the absence of combined n and of o2. we induced nitrogenase by transfer to anaerobic n-free medium and studied the effect of mo starvation on nitrogenase activity and synthesis. activity was first detected within 3 h after transfer by the acetylene reduction assay in controls, increasing for at least 25 h. cells grown on nitrate and mo and then transferred to n-free, mo-free medium produced 8% of the control nitrogenase ac ...197896092
purification and properties of nitrogenase from the cyanobacterium, anabaena cylindrica.the nitrogenase complex was isolated from nitrogen-starved cultures of anabaema cylindrica. sodium dithionite, photochemically reduced ferredoxin, and nadph were found to be effective election donors to nitro genase in crude extracts whereas hydrogen and pyruvate were not. the km for acetylene in vivo is ten-fold higher than the km in vitro, whereas this pattern does not hold for the non-heterocystous cyanobacterium, plectonema boryanum. this indicates that at least one mechanism of oxygen prote ...1979111934
[electron microscopic study of thylakoid structure in cyanobacteria].two or three thylakoids can be detected in synechococcus elongatus, strain 58, and plectonema boryanum if sections are successful. peripheral thylakoids sometimes seem to be connected with the cytoplasmic membrane. partitions and septa, as well as small electron-dense granules typical of cells which underwent lysis, are found in the intrathylakoidal space. branching of thylakoids is described. particles 16 and 11 nm in size whose possible nature is discussed can be discerned on the fracture face ...1979112360
[ultrafine structure of lpp-1 cyanophage-infected plectonema boryanum cells].the interaction of the cyanophage lpp-1 with the trychomous blue-green alga plectonema boryanum was studied. the stage of formation and maturation of phage particles was found to be preceded with the production of the dna-phage pool similar in its morphology with that in trychomous bacteria of the order caryophanales. phagolysis of pl. boryanum cells infected with the phage involved, apart from typical changes in the cytoplast, some distortion in the structure of young, unfinished partitions.1979113652
effect of ions on the activity of the enzyme alkaline phosphatase from plectonema boryanum.alkaline phosphatase extracted from p. boryanum with lysozyme or polymyxin b treatment was used in a comparative study of cell bound and cell free enzyme. the effects of various ions on enzyme activity were tested. calcium was found to enhance activity to the greatest degree stimulating the cell bound alkaline phosphatase 100% and cell free enzyme four-fold. magnesium and potassium also stimulated the activity of cell bound and cell free enzyme. other ions were found to be inhibitory to varying ...1979120924
the purification and properties of superoxide dismutase from a blue-green alga.soluble extracts of plectonema boryanum have been shown to contain a single, electrophoretically distinct, superoxide dismutase. the enzyme has been isolated and has been found to be an iron-containing enzyme similar to that described from the periplasm of escherichia coli. it contains 1 fe3+/mole of enzyme. the molecular weight was approximately 36 500, and the enzyme appeared to be composed of two subunits of equal size joined by non-covalent interactions. esr data are presented, as are the r ...1975164232
superoxide dismutases from a blue-green alga, plectonema boryanum.iron-containing and manganese-containing superoxide dismutases were found in plectonema boryanum. the mn-enzyme occupies about 10% of total activity. the fe-enzyme was purified to near homogeneity. it contains 2 atoms of iron per mol. its molecular weight is 41,700 and it is composed of two subunits of identical molecular weight without disulfide linkage. amino acid composition is presented. electron paramagnetic resonance spectrum revealed that iron occurs in a high spin ferric form and in some ...1975164453
purification and primary structure of cytochrome f from the cyanobacterium, plectonema boryanum.the amino acid sequence of the soluble c-type cytochrome, cytochrome f, from the cyanobacterium plectonema boryanum (also called phormidium luridum or schizothrix calcicola) has been determined. the proposed sequence consists of one polypeptide chain of 85 residues and has three asn-gly linkages. partly due to the presence of these asn-gly bonds, which readily undergo rearrangement, proteolytic digestion on the small amount of protein available was unsatisfactory. the structure was determined pa ...1977199428
temperature dependence on the delayed fluorescence of chlorophyll a in blue-green algae.1. the delayed fluorescence of chlorophyll a was measured with a phosphoroscope by changing the temperature in a range of room temperatures in intact cells of blue-green algae, anacystis nidulans, two strains of anabaena variabilis and plectonema boryanum, and other kinds of algae, cyanidium caldarium and chlorella pyrenoidosa. the induction of delayed fluorescence remarkably depended on the temperature of measurment. nevertheless, the induction pattern was characterized by three levels of inten ...1977403943
[structure and cell division of the blue-green alga plectonema boryanum].our data on the structure of the blue-green alga plectonema boryanum, as well as the analysis of the data of other authors, show that its cells resemble bacterial cells in the basic features of their fine structure (the cell wall, cytoplasmic membrane, nucleoid, membraneous formations, ribosomal apparatus). besides the organelles typical of blue-green algae, organelles similar to mesosomes and formations looking like lysosomes were found in pl. boryanum. data obtained in the course of the format ...1977408585
ultrastructural localization of alkaline phosphatase in the blue-green bacterium plectonema boryanum.histochemical techniques applied at the ultrastructural level have clearly established the periplasmic space as the site of alkaline phosphatase activity in plectonema boryanum. considerable enzyme activity is found after the organism is placed in a phosphate-free medium for 5 days. this activity is found only in the cellular fraction of the culture with no activity present in the culture medium. localization of the site of enzyme activity in cells was investigated by a modification of the metho ...1977411786
ethionine-resistant mutants of the filamentous blue-green alga plectonema boryanum.plectonema boryanum mutants that are resistant to ethionine are unable to incorporate ethionine into acid-precipitable material. ethionine causes bleaching of chlorophyll in sensitive cells.1978417071
active transport of glucose and alpha-methylglucoside in the cyanobacterium plectonema boryanum. 1978417083
coevolution of a virus-alga system.plectonema boryanum, a filamentous blue-green alga, was cloned and then allowed to reach a steady state in a quasi-continuous culture in the presence of the algal virus, lpp-1. the culture was maintained for 3.5-month period during which time at least four distinct culture lysings were evident. after the fourth lysis the culture reached a steady-state level which was identical in its algal concentration to the preinfection level. upon testing the characteristics of the evolved alga and virus ...1975803818
heterotrophic growth of the filamentous blue-green alga plectonema boryanum.plectonema boryanum can grow in the dark with ribose, sucrose, mannitol, maltose, glucose, or fructose. cell doubling times with 10 mm substrate are the following: 5 days with ribose, 6 days with sucrose or mannitol, 10 days with maltose, 12 days with glucose, and 13 days with fructose; with ribose plus 0.1% casamino acids it is 2.5 days. dark-grown cells appear mophologically similar to light-grown cells. cells grown in the dark for several years remain pigmented and resume photoautotrophic gro ...1975803826
heat induction of the blue-green alga plectonema boryanum lysogenic for the cyanophage splcts1. 1975806167
photoreactivation of uv-irradiated blue-green algae and algal virus lpp-1.ultraviolet (uv) sensitivity and photoreactivation of blue-green algae cylindrospermum sp., plectonema boryanum, spores of fischerella muscicola and algal virus (cyanophage) lpp-1 were studied. the survival value after uv irradiation of filaments of cylindrospermum sp. and virus lpp-1 showed exponential trend and these were comparatively sensitive towards uv than f.muscicola and p.boryanum. photoreactivation of uv-induced damage occurred in black, blue, green, yellow, red and white light in cyli ...1975807175
[effect of several plant growth regulators on various prokaryotes and their viruses].26 plant growth regulators including herbicides were investigated in their effect on the multiplication of escherichia coli, bacillus subtilis, and the blue-green alga plectonema boryanum as well as the rna phages m 12 and qbeta and the dna phages lambda, phi 105, and lpp-1 employing the agar diffusion method. nearly all of the compounds inhibited and/or stimulated one or some of the prokaryotes tested. the most frequent and strongest effects occurred in pl. boryanum, the least effects in e. col ...1975809932
lysogeny of blue-green alga plectonema boryanum by long tailed virus.lysogeny and its induction with mitomycin c by the long tailed virus is reported. the active virus was liberated in the medium during the growth period and ability of trichomes to produce virus was not reduced by treatment with edta.1975810657
sensitization of algal virus to uv by the incorporation of 5-bromouracil and mutations of host alga plectonema boryanum.ultraviolet light (uv) sensitivity and photoreactivation of algal virus (cyanophage) lpp-1 were studied after multiplication in host alga plectonema boryanum in presence of 5-bromouracil (5-bu) alone and in conjunction with sulfanilamide. virus particles containing 5-bu were more sensitive towards uv and also showed low photoreactivation. there was less incorporation of 5-bu in virus without pretreatment of host alga with sulfanilamide, an inhibitor of thymine synthesis. 5-bu-induced short trich ...1975813403
metabolic aspects of lpp cyanophage replication in the cyanobacterium plectonema boryanum.cyanophage lpp1g is reproduced at the same yield in heterotrophic conditions (dark, glucose) as in photoautotrophic conditions; aerobiosis is required for dark cyanophage replication. exogenous glucose is not required for the cyanophage replication in the dark in heterotrophically grown cells. in photoautotrophically grown cells, the maximum burst size in dark and glucose is delayed for a period corresponding to glucose uptake induction. cyanophage lpp2spi replication occurs in conditions where ...1976816372
protein synthesis following infection of the blue-green alga plectonema boryanum with the temperature virus spi and its ts mutants. 1976820066
dna sequence and analysis of a cryptic 4.2-kb plasmid from the filamentous cyanobacterium, plectonema sp. strain pcc 6402.the 4194-bp plasmid, prf1, from plectonema sp. strain pcc 6402 was completely sequenced and analyzed. seven potential open reading frames were identified. the predicted amino acid sequence of open reading frame c (orf c) had identities of 34, 29, and 25% with rep b from the staphylococcus aureus plasmid, pub110; rep from the bacillus amyloliquefaciens plasmid, pftb14; and protein a from the s. aureus plasmid, pc194, respectively. a 75-amino-acid region conserved in these proteins (rep b, rep, an ...19921409974
restriction analysis and quantitative estimation of methylated bases of filamentous and unicellular cyanobacterial dnas.the dnas of strains of three cyanobacterial genera (anabaena, plectonema, and synechococcus) were found to be partially or fully resistant to many restriction endonucleases. this could be due to the absence of specific sequences or to modifications, rendering given sequences resistant to cleavage. the latter explanation is substantiated by the content of n6-methyladenine and 5-methylcytosine in these genomes, which is high in comparison with that in other bacterial genomes. dcm- and dam-like met ...19882832390
studies on nitrate reductase of clostridium perfringens. iv. identification of metals, molybdenum cofactor, and iron-sulfur cluster.nitrate reductase of clostridium perfringens was purified by an improved method using immuno-affinity chromatography. the purified preparation contained mo, fe, and acid-labile sulfide; the mo content was 1 mol per mol and the fe 3.7 mol per mol of the enzyme. the inactive enzyme obtained from cells grown in the presence of tungstate did not hold mo but contained 1 mol of w. the content of fe was not increased. the presence of molybdenum cofactor in the nitrate reductase was indicated by the for ...19872884214
cytotoxic, fungicidal nucleosides from blue green algae belonging to the scytonemataceae.tubercidin, toyocamycin, and the corresponding 5'-alpha-d-glucopyranose derivatives of the nucleosides are frequently responsible for much of the cytotoxicity and antimycotic activity associated with extracts of cultured cyanophytes belonging to the family scytonemataceae. the 5'-alpha-d-glucopyranoses of tubercidin and toyocamycin, for example, are the major cytotoxic and fungicidal nucleosides in fijian plectonema radiosum and hawaiian tolypothrix tenuis, respectively.19883139604
isolation and characterization of a new virus infecting the blue-green alga plectonema boryanum. 19744132243
the characterization of c-phycocyanin from an extremely halo-tolerant blue-green alga, coccochloris elabens.c-phycocyanin was isolated and purified from a uni-algal culture of an extremely halo-tolerant blue-green alga, coccochloris elabens. this alga can be grown under laboratory conditions in 25% (w/v) nacl. purified halophile phycocyanin was characterized by amino acid analysis and the measurement of sedimentation velocity, fluorescence polarization and immunodiffusion as a function of protein concentration, ph and ionic strength. the results were compared with those of studies of phycocyanin isola ...19734198583
[isolation and study of the dna from the protoplasts of plectonema boryanum]. 19724199954
[electron microscopic study of the dna of the virus of plectonema boryanum]. 19724199955
[respiration of the blue-green alga plectonema boryanum]. 19734202813
[phenomonologic features of photomodification of radiation injuries in the blue-green alga plectonema boryanum]. 19734203882
nitrogenase activity and photosynthesis in plectonema boryanum.nitrogen-starved plectonema boryanum 594 cultures flushed with n(2)/co(2) or a/co(2) (99.7%/0.3%, vol/vol) exhibited nitrogenase activity when assayed either by acetylene reduction or hydrogen evolution. oxygen evolution activities and phycocyanin pigments decreased sharply before and during the development of nitrogenase activity, but recovered in the n(2)/co(2) cultures after a period of active nitrogen fixation. under high illumination, the onset of nitrogenase activity was delayed; however, ...19744209777
[adsorption of cyanophage lpp-1 on cells of the blue-green alga plectonema boryanum]. 19744217047
phosphate metabolism in blue-green algae. i. fine structure of the "polyphosphate overplus" phenomenon in plectonema boryanum. 19744371465
lysogeny of the blue-green alga plectonema boryanum by lpp2-spi cyanophage. 19724621726
[intercellular interactions and recovery of the population of plectonema boryanum blue-green algae following gamma-irradiation]. 19724624190
the effect of antibiotic stress on protein synthesis in the establishment of lysogeny of plectonema boryanum. 19724625018
light effect on the internal osmotic pressure of the blue-green algae plectonema boryanum and phormidium luridum. 19724629378
[the dna nucleotide composition of the blue-green alga plectonema boryanum and of lpp-1 virus]. 19734633760
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.19694891858
the reproductive cycle of cyanophage lpp1-g in plectonema boryanum and its dependence on photosynthetic and respiratory systems. 19704985559
morphology of a virus of blue-green algae and properties of its deoxyribonucleic acid.the morphology of safferman's virus of blue-green algae (phycovirus lpp-1) has been studied by electron microscopy and physicochemical methods. the virion has a short (100 to 200 a long, 150 a in diameter) forked tail, with an outer sheath, an inner core, and a capital attached to one of the vertices of a polyhedral head. the head capsid edge-to-edge distance is 600 a, based upon internal calibration of the magnification in electron micrographs by use of the line-line spacing of catalase crystal ...19674990040
[interrelations between populations of the blue-green alga plectonema boryanum gom. and cyanophage lpp-l]. 19704990618
nitrogenase activity in the blue-green alga plectonema boryanum strain 594. 19704992219
lpp-1 infection of the blue-green alga plectonema boryanum. 3. protein synthesis.the structural proteins of mature lpp-1 particles and the patterns of protein synthesis after lpp-1 infection have been examined by electrophoresis on sodium dodecyl sulfate polyacrylamide gels. structural proteins account for 35% of the lpp-1 genome, and proteins that would require about 65% of the total coding capacity have been detected after infection. the major head proteins have molecular weights of 39,000 and 13,000, whereas the major tail protein is an 80,000-molecular-weight species. ho ...19704993000
endogenous dark respiration of the blue-green alga, plectonema boryanum.endogenous dark respiration in the blue-green alga plectonema boryanum is markedly affected by preincubation in the light: it can be increased from a basal rate of 5 nmoles of o(2) to 55 nmoles of o(2) per mg of cell protein per min after exposure of the cells to light for 8 to 10 hr. under conditions of enhanced dark respiration, cyanophage multiplication in the dark increases drastically and approaches the cyanophage yields obtained in photosynthesizing plectonema cells. this implies that the ...19714994602
laser-induced reactions of p700 and cytochrome f in a blue-green alga, plectonema boryanum. 19714995801
lysogeny of a blue-green alga, plectonema boryanum. 19715000129
a thermosensitive cyanophage (lppi-g) attacking the blue-green alga plectonema boryanum. 19715001516
properties of ribulose-1,5-diphosphate carboxylase (carboxydismutase) from chinese cabbage and photosynthetic microorganisms.ribulose-1,5-diphosphate carboxylase (carboxydismutase) was prepared from chinese cabbage [brassica petsai (parl)] and the k(m) values and molecular weight were determined. these parameters were found to be in good agreement with values reported for this enzyme from other higher plants. investigation of carboxydismutase activity from the photosynthetic micro-organisms chlamydomonas reinhardi (iu 89+), plectonema boryanum (iu 594), and chromatium strain d showed striking similarity to the higher ...19685700019
effect of cyanophage infection on co2 photoassimilation in plectonema boryanum.cyanophage infection effects a rapid and complete cessation of co(2) photoassimilation in plectonema cells. from the amount of infected cells lysed, it was established that this phenomenon cannot be ascribed to lysis of the host cells either from within or from without. the possibility that the effect is due to nitrogen starvation, induced secondarily by cyanophage multiplication, was ruled out when it was found that nitrogen supplementation did not influence the inhibition. it is suggested that ...19685723527
short-trichome mutant of plectonema boryanum. 19695773043
culture methods for the blue-green alga plectonema boryanum and its virus, with an electron microscope study of virus-infected cells. 19665938887
effect of virus infection on rate of photosynthesis and respiration of a blue-green alga, plectonema boryanum. 19676025065
isolation of "cyanophages" from freshwater ponds and their interaction with plectonema boryanum. 19676025877
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 ...19836298180
resistance of dna from filamentous and unicellular cyanobacteria to restriction endonuclease cleavage.chromosomal dna from nine species of filamentous cyanobacteria as diverse as nostoc, gloeotrichia and plectonema is suggested to be extensively modified (methylated) by its resistance to cleavage by a number of restriction endonucleases. a remarkably similar pattern of dna modification in these species contrasts with the known heterogeneity of their type ii restriction endonuclease content. in particular, nostoc pcc 73102, which lacks detectable sequence-specific endonucleases, is shown to posse ...19846320895
effects of pesticides on cyanobacterium plectonema boryanum and cyanophage lpp-1.cyanobacterium plectonema boryanum iu 594 and cyanophage lpp-1 were used as indicator organisms in a bioassay of 16 pesticides. experiments such as spot tests, disk assays, growth curves, and one-step growth experiments were used to examine the effects of pesticides on the host and virus. also, experiments were done in which host or virus was incubated in pesticide solutions and then assayed for pfu. p. boryanum was inhibited by four herbicides: 3-(3,4-dichlorophenyl)-1,1-dimethylurea (dcmu), 1, ...19846430230
utilization of morphometric analysis in evaluating response of plectonema boryanum (cyanophyceae) to exposure to eight heavy metals. 19826808934
nitrogenase activity and membrane electrogenesis in the cyanobacterium plectonema boryanum.the relationships between nitrogenase activity (acetylene reduction) and the transplasmalemma proton electrochemical potential gradient (delta muh+) have been investigated using the non-heterocystous filamentous cyanobacterium plectonema boryanum. by selectively modifying the chemical (delta ph) and electrical (delta psi) components of delta muh+ under conditions in which the size of the atp pool remained unaffected, nitrogenase activity was found to be dependent on, or regulated by delta psi. w ...19826814911
a novel nitrite reductase gene from the cyanobacterium plectonema boryanum.the gene (nira) for nitrite reductase was cloned from the nonheterocystous, filamentous cyanobacterium plectonema boryanum. the predicted protein consists of 654 amino acids and has a calculated molecular weight of 72,135. the deduced amino acid sequence from positions 1 to 511 is strongly similar to the entire sequence of the ferredoxin-dependent nitrite reductases from other phototrophs, while the remainder of the protein is unique to the plectonema nitrite reductase. the c-terminal portion of ...19957592378
characterization of a small cryptic plasmid, ppf1, from phormidium foveolarum and vector construction.the 1509 bp cryptic plasmid, ppf1, from phormidium foveolarum, a strain of filamentous cyanobacteria of the lpp group, was completely sequenced. the ppf1 nucleotide sequence had 97.8% overall similarity with that of a small plasmid from plectonema boryanum. the structural organization of ppf1 and vector construction are discussed.19937764277
characterization of four superoxide dismutase genes from a filamentous cyanobacterium.by using an oligonucleotide probe constructed from a conserved region of amino acids located in the carboxyl-terminal end of superoxide dismutase (sod) proteins, four sod genes were cloned from the cyanobacterium plectonema boryanum utex 485. one of these genes, designated sodb, encoded an fesod enzyme, while the remaining three genes, designated soda1, soda2, and soda3, encoded mnsod enzymes. to investigate the expression of these four genes, total cellular rna was isolated from p. boryanum ute ...19957860607
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 ...19947918657
uncoupling of photosystems during light dependent dinitrogen fixation by a non-heterocystous cyanobacterium plectonema boryanum.plectonema boryanum grows under microaerobic nitrogen starvation conditions by temporal separation of the oxygen-sensitive nitrogen fixation and the oxygen-evolving photosynthesis. during the nitrogen-fixation phase, depression in light-dependent oxygen evolution results from alterations in the stare of qa/qb complex. the reaction centre in photosystem ii is not oxidised efficiently. light dependence of nitrogenase function under such conditions appears to be related to the coupling of photosyst ...19948002013
characterization of the genome region encoding an fdxh-type ferredoxin and a new 2[4fe-4s] ferredoxin from the nonheterocystous, nitrogen-fixing cyanobacterium plectonema boryanum pcc 73110.a genomic dna region with four consecutive open reading frames, including an fdxh-type gene, has been sequenced and initially characterized for the nonheterocystous nitrogen-fixing cyanobacterium plectonema boryanum pcc 73110. the fdxh gene encodes a [2fe-2s]-type ferredoxin, 98 amino acids in length, with a deduced molecular mass of 10.9 kda. conserved residues include two characteristic lysines at positions 10 and 11, shown recently to be important for interaction with nitrogenase reductase (s ...19948106314
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 ...19948161180
identification of a nifdk-like gene (orf467) involved in the biosynthesis of chlorophyll in the cyanobacterium plectonema boryanum.the frxc gene, which is found in chloroplast dna (ctdna) and in cyanobacteria, encodes a protein that is required for the light-independent reduction of protochlorophyllide (pchlide) to chlorophyllide a (chlide). a dna fragment downstream of frxc in the filamentous cyanobacterium plectonema boryanum was cloned and analyzed. sequencing of the dna fragment revealed an open reading frame (orf) that encoded a protein of 467 amino acid residues (designated orf467), which showed extensive homology to ...19938199775
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 ...19938320214
involvement of acceptor side components of psii in the regulatory mechanism of plectonema boryanum grown photoautotrophically under diazotrophic condition.alternating peaks of photosynthetic activity (p-phase) and nitrogen fixing activity (n-phase) were shown in plectonema boryanum grown under diazotrophic condition in continuous light. in n-phase photosystem i activity increased by 35-45% and oxygen evolution decreased by 70-80% which was partially restored to 45-55% in the presence of 2,6-dichloro-p-benzoquinone. thermoluminescence glow curve in p-phase consists of a major band at 25 degrees c which was shifted to 10 degrees c in n-phase. both t ...19938352756
dna sequence and shuttle vector construction of plasmid pgl3 from plectonema boryanum pcc 6306. 19938441688
[alanine dehydrogenase from the cyanobacterium plectonema boryanum].alanine dehydrogenase activity of plectonema boryanum cells was studied. it was found, that only nad(h) may be used as the coenzyme. kinetical parameters for substrates and coenzymes were determined. 2 ph-optima of action have been established for biosynthetic and anabolic reactions. two isoenzymes of adg were cleaned using the methods of ion-exchange chromatography and isoelectric focusing. some physical-chemical properties were studied: phopt--9-10 and 4.0; temperature optimum -40 degrees c; p ...19958588252
[aspartate kinase from the cyanobacteriium plectonema boryanum infected with the cyanophage lpp-3].the effect of development of cyanophage infection on the activity of aspartate kinase of plectonema boryanum has been studied. it has been determined that activity of aspartate kinase increased during early period of reproduction of cyanophage. it coincided in time with the increase of the level of amino acids of aspartate family. isoenzymes of aspartate kinase were isolated from the infected cells purified and studied. expression of viral genome is accompanied with the appearance of four new is ...19958588253
identification of the chlb gene and the gene product essential for the light-independent chlorophyll biosynthesis in the cyanobacterium plectonema boryanum.we cloned a 6.0-kb hindiii fragment from the cyanobacterium plectonema boryanum using the chloroplast chlb (orf513) gene of the liverwort (marchantia polymorpha) as a probe. an open reading frame (orf508) encoding a polypeptide of 508 amino acid residues was found within the nucleotide sequence of the 4,437-bp hindiii-ecorv subfragment. the deduced amino acid sequence of orf508 shows very high similarity to that encoded by the liverwort chlb gene (72.7%). a mutant, yfb14, in which orf508 was ina ...19968673341
distinct and differently regulated mo-dependent nitrogen-fixing systems evolved for heterocysts and vegetative cells of anabaena variabilis atcc 29413: characterization of the fdxh1/2 gene regions as part of the nif1/2 gene clusters.two different fdxh genes (fdxh1, fdxh2) have been isolated from the nitrogen-fixing, heterocyst-forming cyanobacterium anabaena variabilis atcc 29413. they are part of two different nif gene clusters, nif1 and nif2. fdxh1 encodes the [2fe-2s] ferredoxin that is known as the direct electron donor to nitrogenase in heterocysts, and is very similar to fdxh from anabaena sp. pcc 7120. fdxh2 has more residues in common and shares its oxygen sensitivity with the single fdxh from the non-heterocystous, ...19958709854
positive regulation by nitrite of the nitrate assimilation operon in the cyanobacteria synechococcus sp. strain pcc 7942 and plectonema boryanum.in the absence of fixation of ammonium to glutamine, nitrate and nitrite activated transcription of the nitrate assimilation (nira-nrtabcd-narb) operon of synechococcus sp. strain pcc 7942. in a nitrate reductase-deficient mutant, only nitrite activated transcription, indicating that nitrite is the actual activator of the operon. nitrate and nitrite were also found to activate the transcription of a nitrate assimilation operon in the filamentous nonheterocystous nitrogen-fixing cyanobacterium pl ...19968824636
[effect of reproduction of the lpp-3 cyanophage on glutamate dehydrogenase and glutamine synthetase activity in the cyanobacterium plectonema boryanum].the effect of cyanophage lpp-3 reproduction on glutamate dehydrogenase and glutamine synthetase (gs) in p boryanum cells have been studied. it was determined that the both reactions are intensified by 135% and 220%, accordingly. isoenzymes of gs were purified from native and infected cell of cyanobacteria. their physical-and-chemical properties are different. the cyanophage development probably causes specific modification of the cell enzymes.19958867309
kinesin light chain in a eubacterium.a eubacterial homolog of a kinesin light chain gene has been isolated and characterized from the cyanobacterium plectonema boryanum. although the eubacterial and eukaryotic kinesin light chains are highly similar in amino acid sequence, the eubacterial sequence differs in several distinguishing structural features, including the absence of a putative pest domain and the presence of additional highly conserved imperfect tandem repeats. two soluble kinesin light chain antigens have been identified ...19979212172
cloning of the gene encoding a protochlorophyllide reductase: the physiological significance of the co-existence of light-dependent and -independent protochlorophyllide reduction systems in the cyanobacterium plectonema boryanum.cyanobacteria have two protochlorophyllide (pchlide) reductases catalyzing the conversion of pchlide to chlorophyllide, a key step in the biosynthetic pathway of chlorophylls (chls); a light-dependent (lpor) and a light-independent (dpor) reductase. we found an open reading frame (orf322) in a 2,131-bp ecori fragment from the genomic dna of the cyanobacterium plectonema boryanum. because the deduced amino acid sequence showed a high similarity to those of various plant lpors and the lpor activit ...19989559561
acquisition of a new type of fructose-1,6-bisphosphatase with resistance to hydrogen peroxide in cyanobacteria: molecular characterization of the enzyme from synechocystis pcc 6803.we have previously described that synechococcus pcc 7942 cells contain two fructose-1,6-bisphosphatase isozymes, designated f-i and f-ii the former belongs to a new type of fructose-1,6-bisphosphatase, while the latter is a typical enzyme similar to the cytosolic and chloroplastic forms from eukaryotic cells [tamoi et al., arch. biochem. biophys., 334, 1996, 27-36]. the genes of f-i and f-ii were found in three species of cyanobacteria, synechocystis pcc 6803, anabaena 7120, and plectonema borya ...19989602137
multiple oligomeric forms of glucose-6-phosphate dehydrogenase in cyanobacteria and the role of opca in the assembly process.multiple molecular forms of glucose-6-phosphate dehydrogenase (g6pdh) were detected by activity staining in non-denaturing polyacrylamide gels of cell-free extracts from a range of cyanobacteria including anabaena sp. pcc 7120, synechococcus sp. pcc 7942, plectonema boryanum pcc 73110, synechocystis sp. pcc 6803, nostoc sp. mac pcc 8009 and the marine strain synechococcus sp. wh7803. in most of the species tested, the profile of g6pdh activities was modulated by the growth of the cells in the pr ...19989639925
clpb in a cyanobacterium: predicted structure, phylogenetic relationships, and regulation by light and temperature.the sequence of a genomic clone encoding a 100-kda stress protein of plectonema boryanum (p-clpb) was determined. the predicted polypeptide contains two putative atpase regions located within two highly conserved domains (n1 and n2), a spacer region that likely forms a coiled-coil domain, and a highly conserved consensus ck2 phosphorylation domain. the coiled-coil region and the putative site of phosphorylation are not unique to p-clpb; they are present in all clpb sequences examined and are abs ...19989748452
cloning and inactivation of genes encoding ferredoxin- and nadh-dependent glutamate synthases in the cyanobacterium plectonema boryanum. imbalances in nitrogen and carbon assimilations caused by deficiency of the ferredoxin-dependent enzymeglutamate synthase (gogat) is a key enzyme in the assimilation of inorganic nitrogen in photosynthetic organisms. we found that, like higher plants, the facultative heterotrophic cyanobacterium plectonema boryanum had ferredoxin (fd)- and nadh-dependent gogats. the genes glsf, gltb, and gltd were cloned, and structural analyses and target mutageneses demonstrated that glsf encoded fd-gogat and that gltb and gltd encoded the two subunits of nadh-gogat. all three mutants lacking one of the gogat g ...199910318681
heavy metal uptake by polyphosphate bodies in living and killed cells of plectonema boryanum (cyanophycae).the study was conducted to determine whether living or killed cell polyphosphate bodies (ppb) would sequester more of several heavy metals. living and heat- or glutaraldehyde-killed cells were exposed to 20 ppm of zn, pb, mn and al. air-dried cells on formvar-coated grids were first observed in the transmission electron microscope. the unit was then switched to the scanning transmission mode of operation with the spot setting. x-rays were collected on an energy dispersive x-ray spectrometer and ...199810399343
differential expression of photosynthesis and nitrogen fixation genes in the cyanobacterium plectonema boryanum.the filamentous non-heterocystous cyanobacterium plectonema boryanum fixes dinitrogen at a high rate during microaerobic growth in continuous illumination by temporal separation of oxygen-evolving photosynthesis and oxygen-sensitive dinitrogen fixation. the onset of nitrogen fixation is preceded by a depression in photosynthesis that establishes a sufficiently low level of dissolved oxygen in the growth medium. a several-fold reduction in the level of transcripts coding for phycocyanin (cpcba) a ...200010712536
[the isolation, purification and cloning of the psm1 plasmid from the cyanobacterium plectonema boryanum].three methods of plasmids isolation from the cells of cyanobacteria: plectonema boryanum 465, p. nostocorum 636, p. nostocorum 638, p. edaphicum 262, plectonema sp. 456, phormidium uncinatum 528, anabaena variabilis 458 and synechococcus cedrorum 750 have been approved. the method of plasmids isolation by 1 m nacl salting out was used for plasmid screening. all the strains studied contained large, above 55 kb plasmids, small plasmids (1.5 kb) were found in the cells of p. boryanum 465 and p. nos ...200010872285
excitation energy transfer from phycobilisomes to photosystems: a phenomenon associated with the temporal separation of photosynthesis and nitrogen fixation in a cyanobacterium, plectonema boryanum.plectonema boryanum shows temporal separation of photosynthesis and nitrogen fixation under diazotrophic conditions. low temperature fluorescence studies have shown that in vivo the nitrogen fixing and photosynthesizing cells are adapted to 'state 2' and 'state 1', respectively. during nitrogen fixation phycobilisomes seem to transfer excitation energy to photosystem i whereas during oxygenic photosynthesis the energy is transferred to photosystem ii. the state 2 adapted n-phase cells failed to ...200010924907
surface charge density and light-scattering of the plectonema boryanum spheroplasts.the electrokinetic properties of spheroplasts from the cyanobacterium plectonema boryanum were examined by particle microelectrophoresis technique. the electrophoretic mobility (epm) of the particles was determined after incubation with cacl2 in dependence of iron content in culture media as follows: an iron sufficient medium ('control' variant), an iron-deficient medium ('fe-starved' variant) and an excess of iron supply medium ('20 x fe' variant). strong increase in epm was observed with micro ...199910228594
therapeutical effect of modified adamantane copolymer compounds: study of molecular mechanisms.copolymers of n-polyvinylpyrrolidone-acrylic acid (ab-1) and adamantane derivatives are known to possess marked antiviral activity in in vitro and in ovo models. among the constructed preparations of ab-1 modified by adamantane derivatives some, especially ab-4 (modified by deitiforin), were found to show more extended antiviral activity and to inhibit markedly virus reproduction in susceptible permissive cell cultures and chicken embryos. in ab-4 treated cells and allantoic sacs, virus titers ( ...200111440176
quantitative analysis of the elemental composition and the mass of bacterial polyphosphate bodies using stem edx.the quantitative analysis of laboratory grown organisms (plectonema boryanum and staphylococcus aureus) revealed that a typical in vivo polyphosphate body (ppb) contains o (4.3 x 10(-8) microg), c (1.2 x 10(-8) microg), p (6.7 x 10(-9) microg), mg (1.3 x 10(-9) microg), ca (6.7 x 10(-10) microg), k (6.7 x 10(-10) microg), fe (6.0 x 10(-10) microg), s (5.4 x 10(-10) microg) and al (5.9 x 10(-10) microg). quantitative x-ray analysis of samples from nature showed ppb contain o (1.63 x 10(-8) microg ...200111522129
the evolution of glutathione metabolism in phototrophic microorganisms.of the many roles ascribed to glutathione (gsh) the one most clearly established is its role in the protection of higher eucaryotes against oxygen toxicity through destruction of thiol-reactive oxygen byproducts. if this is the primary function of gsh then gsh metabolism should have evolved during or after the evolution of oxygenic photosynthesis. that many bacteria do not produce gsh is consistent with this view. in the present study we have examined the low-molecular-weight thiol compositio ...198711542078
[physical mapping of plasmid psm1 of the cyanobacterium plectonema boryanum gom. strain calu 465].a physical map of plasmid psm1 has been compiled as a result of restriction analysis of pbsmi isolated from the cells of cyanobacterium plectonema boryanum 465. a comparative analysis of the restriction sites localization in dna of plasmid psm1 with site topology of plasmids pgl3 of p. boryanum and ppf1 of phormidium foveolarum indicates to high degree of these plasmids homology.200111692681
degradation of crude oil by marine cyanobacteria.the marine cyanobacteria oscillatoria salina biswas, plectonema terebrans bornet et flahault and aphanocapsa sp. degraded bombay high crude oil when grown in artificial seawater nutrients as well as in plain natural seawater. oil removal was measured by gravimetric and gas chromatographic methods. around 45-55% of the total fractions of crude oil (containing 50% aliphatics, 31% waxes and bitumin, 14% aromatics and 5% polar compounds) were removed in the presence of these cultures within 10 days. ...200111759698
[construction of the shuttle vector psts1 and development of the method of its introduction into the cells of the cyanbacterium plectonema boryanum calu 465].it has been shown that cells of trichoma cyanobacterium plectonema boryanum g o m. strain calu 465 do not possess natural resistance to antibiotics ampicyllin, chloramphenicol, streptomycin and canamycin. a shuttle vector psts1 has been constructed on the basis of cyanobacterial plasmid psm1 and vector pbr 322. conditions have been developed and conjugative transfer of psts1 to the cells of cyanobacterium p. boryanum has been performed. as the result of expression of beta-lactamase gene psts1 th ...200111785421
the presence of an iron-sulfur cluster in adenosine 5'-phosphosulfate reductase separates organisms utilizing adenosine 5'-phosphosulfate and phosphoadenosine 5'-phosphosulfate for sulfate assimilation.it was generally accepted that plants, algae, and phototrophic bacteria use adenosine 5'-phosphosulfate (aps) for assimilatory sulfate reduction, whereas bacteria and fungi use phosphoadenosine 5'-phosphosulfate (paps). the corresponding enzymes, aps and paps reductase, share 25-30% identical amino acids. phylogenetic analysis of aps and paps reductase amino acid sequences from different organisms, which were retrieved from the genbank(tm), revealed two clusters. the first cluster comprised know ...200211940598
the heterocyst-specific fdxh gene product of the cyanobacterium anabaena sp. pcc 7120 is important but not essential for nitrogen fixation.to clarify the role of the heterocyst-specific [2fe-2s] ferredoxin in cyanobacterial nitrogen fixation, mutational analysis of the anabaena 7120 fdxh gene region was carried out. first, the dna sequence of the wild-type 3509-bp ecori fragment downstream of the fdxh gene was determined. genes homologous to orf3 from the fdxh gene regions of a. variabilis and plectonema boryanum, the mop genes of clostridium pasteurianum encoding molybdo-pterin binding proteins, and orf3 from the a. variabilis hyd ...19979079890
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