| [relation of the growth of anabaena variabilis cyanophages to photosynthesis and respiration]. | cyanophages a-1 (l) and a-4c (l) grow within the cells of anabaena variabilis under aerobic conditions in the dark in the presence of endogenous or exogenous (surcose) sources of energy. dnp inhibits the growth of cyanophages in the light and almost completely supresses it in the dark, o-phenanthroline entirely supresses the growth in both cases. dcmu has almost no effect on the yield of the virus in the light. virus particles can apparently be synthesized at the account of the energy of both ox ... | 1977 | 409909 |
| physical properties of blue-green algae: ultracentrifugation and electron microscope studies. | | 1977 | 410073 |
| phototrophic prokaryotes: the cyanobacteria. | | 1977 | 410354 |
| phototrophic green and purple bacteria: a comparative, systematic survey. | | 1977 | 410355 |
| preliminary crystallographic investigations of two phycobiliproteins. | single crystal x-ray diffraction investigations are in progress on two phycobiliproteins. c-phycocyanin from anabaena variabilis crystallizes in space group p63 with a = b = 154 a and c = 40 a. the crystallographic asymmetric unit is (alphabeta)2 with a total molecular mass of 7.0-10(4) daltons. b-phycoerythrin from porphyridium cruentum crystallizes in space group r3 with a = b = 189 a and c = 60 a. this molecule has the unusual molecular stoichiometry (alphabeta)6gamma and the crystallographic ... | 1977 | 410813 |
| the colonial rock-forming microfossils of the bohemian upper proterozoic (czechoslovakia), 'bohemipora pragensis' n.g., n.sp. | large amounts of well preserved microfossils have been reported from the cherts of the upper proterozoic of the bohemian massif (middle europe). they resemble those described by cayeux (1894) from the upper proterozoic (brioverian) of bretagne (france). it is shown, unlike the views of cayeux and his followers (deflandre, 1955, and graindor 1957), that the observed structures did not belong to individuals but to colonies of filamentous prokaryotic organisms, most probably blue-green algae (cyano ... | 1977 | 411095 |
| hydrogen formation by marine blue-green algae. | | 1977 | 411686 |
| 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 ... | 1977 | 411786 |
| [degradation of pastures in the region of n'djamena (republic of chad) in relation to the presence of cyanophycees psammophiles. preliminary study]. | | 1977 | 412237 |
| anaerobic and aerobic hydrogen gas formation by the blue-green alga anabaena cylindrica. | an investigation was made of certain factors involved in the formation of hydrogen gas, both in an anaerobic environment (argon) and in air, by the blue-green alga anabaena cylindrica. the alga had not been previously adapted under hydrogen gas and hence the hydrogen evolution occurred entirely within the nitrogen-fixing heterocyst cells; organisms grown in a fixed nitrogen source, and which were therefore devoid of heterocysts, did not produce hydrogen under these conditions. use of the inhibit ... | 1977 | 412467 |
| structural studies on phycobiliproteins. i. bilin-containing peptides of c-phycocyanin. | | 1978 | 412846 |
| structural studies on phycobiliproteins ii. c-phycocyanin: amino acid sequence of the beta subunit. specific cleavage of the alpha subunit. | | 1978 | 412848 |
| structural studies on phycobiliproteins iii. comparison of bilin-containing peptides from the beta subunits of c-phycocyanin, r-phycocyanin, and phycoerythrocyanin. | | 1978 | 412849 |
| the regulation of stable rna synthesis in the blue-green alga anacystis nidulans: effect of leucine deprivation and 5-methyltryptophan inhibition. | the expression of phenomena associated with the bacterial function controlling rna synthesis was studied in leucine-deprived or 5-methyltryptophan-treated cultures of anacystis nidulans. both procedures retarded cell growth, rna and protein accumulation, elicited the accumulation of high intracellular concentrations of guanosine 5'-diphosphate-3'-diphosphate(ppgpp)and guanosine5'-triphosphate-3'-diphosphate(pppgpp),and promoted a regime of non-coordinate synthesis of stable and messenger rna. th ... | 1977 | 412917 |
| 2-aminoadenine is an adenine substituting for a base in s-2l cyanophage dna. | | 1977 | 413053 |
| comparative analysis of action spectra of glycolate excretion ("photorespiration") and photosynthesis in the blue-green alga anacystis nidulans. | | 1977 | 413123 |
| on the morphology and ultrastructure of the cell wall of spirulina platensis. | the cell wall of the blue-green alga spirulina platensis was studied with the electron microscope using ultra-thin sectioning, shadowing, carbon-replication or freeze-etching techniques for specimen preparation. the cell wall could be resolved into four layers, l-i through l-iv. the l-i and l-iii layers contain fibrillar material. the septum is a three-layered wall: an l-ii layer sandwiched between l-i layers. the shape in vitro of isolated septa might be an artifact due to the preparation techn ... | 1977 | 413479 |
| effects of long-term treatment with acetylene on nitrogen-fixing microorganisms. | long periods of experimental incubation with acetylene led to a multifold enhancement of acetylene-reducing activity in anabaena cylindrica, anabaenopsis circularis, rhodospirillum rubrum, and azotobacter vinelandii. rates of acetylene reduction showed a gradual increase and reached a peak after 2 to 6 h of continuous incubation under acetylene. thereafter, enzyme activity rapidly declined. a similar enhancement of ethylene production was observed when pretreatment with acetylene was interrupted ... | 1977 | 413480 |
| production of volatile sulfur compounds during the decomposition of algal mats. | blue-green algal mats incubated anaerobically rapidly produce large amounts of volatile sulfur compounds, including hydrogen sulfide, methyl mercaptan, and dimethyl sulfide. the major organic sulfur compound is methyl mercaptan, in contrast to previous results with marine eucaryotic algae. light inhibited production of volatile sulfur compounds, apparently because the algae then produced o2, rendering the system aerobic. | 1977 | 413485 |
| effect of temperature on the adsorption and one-step growth of the nostoc virus n-1. | this study was an attempt to observe the effects of temperature on adsorption and one-step growth of the virus n-1 infecting the nitrogen-fixing cyanobacterium nostoc muscorum. adsorption rate was found to maximum at 40 degrees c whereas no adsorption occurred at 10 degrees c. the q10 value was about 2.03 and the energy of activation, ea was 16.3 kcal/mole for the adsorption process. the development cycle of the virus was temperature sensitive. with increase in temperature, a gradual increase in ... | 1977 | 413522 |
| effect of carbon dioxide on pigment and membrane content in synechococcus lividus. | the effect of carbon dioxide on pigment and membrane content in synechococcus lividus was studied by depriving cells of co2 and examining cell populations biochemically and by electron microscopy. after 120 h of co2 deprivation, s. lividus lost all detectable chlorophyll a and c-phycocyanin. such bleached cultures were "mustard yellow", the result of approximately 1.8 times more carotenoid per cell than green control cultures. although cells from beached cultures appeared morphologically identic ... | 1977 | 413524 |
| identification of a non-magnetic iron centre and an iron-storage or -transport material in blue--green algal membranes by mössbauer spectroscopy. | at least two species of iron were identified in crude membrane preparations of the blue-green algae chlorogloea fritschii and anacystis nidulans by mössbauer spectroscopy. one species was non-magnetic with chemical shift more characteristic of a ferredoxin-like centre than of any known low-spin fe(ii) biological compounds. studies on cells grown under depleted-iron conditions show the other iron species to be part of the system for iron metabolic transport and/or storage. | 1977 | 413540 |
| preparation of chlorophyll a, chlorophyll b and bacteriochlorophyll a by means of column chromatography with diethylaminoethylcellulose. | | 1978 | 413574 |
| changes in photosynthetic activity in the cyanobacterium chlorogloea fritschii following transition from dark to light growth. | the cyanobacterium chlorogloea fritschii loses photosystem ii activity, measured by delayed fluorescence and oxygen evolution, during dark heterotrophic growth, but retains photosystem i, measured as light induced epr signals. following transition to the light, photosystem ii recovers in two stages, the first of which does not require protein synthesis. new photosystem i reaction centres are not synthesised until after net chlorophyll synthesis has commenced. carbon dioxide fixation recovery com ... | 1978 | 413576 |
| transport of d-glucose and 3-o-methyl-d-glucose in the cyanobacteria aphanocapsa 6714 and nostoc strain mac. | 1. the cyanobacterium aphanocapsa 6714 which grow in the dark on d-glucose, will take up d-glucose and the analogue 3-o-methyl-d-glucose; uptake of each of these compounds was inhibited competitively by the other and by 6-deoxy-d-glucose. 2. this cyanobacterium accumulated 3-o-methyl-d-glucose up to 100-fold relative to the medium but did not modify or metabolize it to a significant degree. 3. intracellular 3-o-methyl-d-glucose was rapidly displaced from aphanocapsa 6714 by exogenous d-glucose a ... | 1978 | 413715 |
| tubular elements - a new structure in blue-green algal cells. | new cell inclusions, 'tubular elements' are described from the blue-green alga calothrix marchica. these structures are found in about 20% of all cells observed. they are 18-22 nm in diameter, apparently composed of sub-units of which the estimated number, as seen in transverse section, is 8-10. | 1977 | 413838 |
| adsorption of cyanophage as-1 to unicellular cyanobacteria and isolation of receptor material from anacystis nidulans. | cells of unicellular cyanobacteria of typological group ia, containing approximately 50 mol% guanine + cytosine (g+c) in their dna (r. y. stanier, r. kunisawa, m. mandel, and g. cohen-bazire, bacteriol. rev. 35:171-205, 1971), were susceptible to infection by the cyanophage as-1. cyanobacteria of the same typological group, containing approximately 65 mol% g+c in their dna, did not adsorb the cyanophage as-1 or adsorbed it at a low rate. as-1 was not propagated by any of the investigated strains ... | 1978 | 413935 |
| [effect of a sulfur-containing nucleotide-peptide complex on the growth and development of different species of algae]. | | 1977 | 414054 |
| [metabolism of carotenoids during dark and photooxidative degradation in anabaena variabilis]. | changes of carotenoids were studied in the cells of the blue-green alga anabaena variabilis incubated in dark for a long period of time in a phosphate buffer, and also upon photooxidative degradation of the "dark" culture, i. e. a culture that had been grown for 8 days and incubated in the darkness for a certain period of time. incubation in the dark resulted in the formation and accumulation in the cells of two new pigments, xanthophyll-450 and beta,beta-carotene-4,4'-dione, whose content decre ... | 1977 | 414056 |
| some characteristics of two morphological mutants of nostoc linckia induced by nitrosoguanidine. | the blue-green alga nostoc linckia was treated with nitrosoguanidine and two classes of morphological mutant clones were isolated. one class shows certain abnormal phenotypic features of vegetative cells, spores, and heterocysts. it has increased heterocyst frequency and impaired growth rate. the other class exhibits an altered heterocyst spacing pattern. both classes of mutants have reduced nitrogenase activity. | 1977 | 414465 |
| alpha-linolenic acid biosynthesis in cyanidium caldarium. | | 1978 | 414660 |
| photooxidation reactions of diphenylcarbazide and their dcmu-sensitivity in thylakoids of the blue-green alga oscillatoria chalybea. | thylakoids of oscillatoria chalybea are able to split water. the hill reaction of these thylakoids is sensitive to dcmu. diphenylcarbazide can substitute for water as the electron donor to photosystem ii with these fully functioning thylakoids. however, the diphenylcarbazide photooxidation is completely insensitive to 3-(3,4-dichlorophenyl)-n-n'-dimethyl urea (dcmu) at high diphenylcarbazide concentrations. in with tris-treated oscillatoria thylakoids the water splitting capacity is lost and dip ... | 1977 | 414682 |
| hydrogen metabolism in the facultative anoxygenic cyanobacteria (blue-green algae) oscillatoria limnetica and aphanothece halophytica. | two facultative anoxygenic photoautotrophic cyanobacteria, oscillatoria limnetica and aphanothece halophytica were found capable of co2 photoassimilation using molecular hydrogen as electron donor in a photosystem i driven reaction. a. halophytica was also capable of evolving hydrogen from na-dithionite reduced methylviologen in a light independent reaction. | 1978 | 414684 |
| induction of anaerobic, photoautotrophic growth in the cyanobacterium oscillatoria limnetica. | anaerobic photoautotrophic growth of the cyanobacterium oscillatoria limnetica was demonstrated under nitrogen in the presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (5micron), a constant concentration of na2s (2.5 mm), and constant ph (7.3). the photoanaerobic growth rate (2 days doubling time) was similar to that obtained under oxygenic photoautotrophic growth conditions. the potential of oxygenic photosynthesis is constitutive in the cells; that of anoxygenic photosynthesis is rapidly (2 ... | 1978 | 415043 |
| [role of free-living nitrogen fixers in the nitrogen balance of soils]. | | 1977 | 415216 |
| structure and molecular organization of the photosynthetic accessory pigments of cyanobacteria and red algae. | | 1977 | 415227 |
| anilines: selective toxicity to blue-green algae. | the blue-green alga agmenellum quadruplicatum (strain pr6) was very sensitive to aniline and p-toluidine (potential environmental toxicants) in an algal lawn assay (the growth of the algal lawn was inhibited with as little as 1 microgram of p-toluidine per disk). assays with seven other species of blue-green algae showed that they had varying sensitivities ranging from 1 to 100 micrograms of p-toluidine. under comparable conditions, 0.5 milligram or more of p-toluidine was needed to inhibit a gr ... | 1978 | 415361 |
| a controlled-temperature apparatus for measurement of hydrogen peroxide production. | | 1978 | 415639 |
| ribosomal rna homologies and the evolution of the filamentous blue-green bacteria. | ribosomal rna (rrna) sequence homology (as determined by comparisons of t1 oligonucleotide catalogs of 32p-labeled 16s rrnas) has been used to assess phylogenetic relationships within the filamentous and unicellular blue-green bacteria, and to identify regions of evolutionary conservatism within blue-green bacterial 16s rrnas. nostoc and fishcherella, representatives of two morphologically distinct and highly differentiated orders, are shown to be as closely related (on the basis of rna sequence ... | 1978 | 416225 |
| variability of nitrogen fixation in some isolates of nostoc linckia. | four clonal isolates of nostoc linckia isolated from different localities were compared with respect to growth, nitrogen content (cellular and extracellular), and pigment composition. a considerable range of variation was observed among these isolates. this indicates the existence of genetically distinct clonal populations of the alga in natural habitats. | 1977 | 416603 |
| changes in photosynthetic rate and pigment content of blue-green algae in lake mendota. | blue-green algal blooms were present in lake mendota (dane county, wis.) from june to november 1976. concentrations of total algal biomass and of particular algal species were monitored and compared with the pigment contents (chlorophyll a and phycocyanin) and photosynthetic rate of the algal populations. the specific photosynthetic rate (micrograms of c fixed per microgram of chlorophyll a per hour) was a good measure of the physiological state of the algae because this quantity increased just ... | 1978 | 416753 |
| on the linkages between chromophore and protein in biliproteins, vii. amino acid sequence in the chromophore regions of c-phycoerythrin from pseudanabaena w 1173 and phormidium persicinum. | bilipeptides from all chromophore regions were prepared by trypsin digestion of c-phycoerythrin from pseudanabaena w 1173 and phormidium persicinum. analytical separation and quantitative determination of bilipeptides was achieved by isoelectric focusing, preparative isolation by gel chromatography and ion-exchange chromatography. amino acid analysis revealed cysteine as the only amino acid common to all chromopeptides. amino acid sequences were determined by edman degradation and the dansyl-edm ... | 1978 | 417013 |
| 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. | 1978 | 417071 |
| amino acid sequence of aphanothece sacrum ferredoxin ii (minor component). structural characteristics and evolutionary implications. | | 1978 | 417074 |
| active transport of glucose and alpha-methylglucoside in the cyanobacterium plectonema boryanum. | | 1978 | 417083 |
| variations in short term products of inorganic carbon fixation in exponential and stationary phase cultures of aphanocapsa 6308. | aphanocapsa 6308 metabolizes both nahco3 and na2co3. the short term incorporation (5-s) metabolic pattern and the patterns of incorporation of bicarbonate for exponential versus stationary phase cultures differ, however. cells were equilibrated for 10 min in air and distilled water prior to injection of either nah14co3 at ph 8.0, or na214co3 at ph 11.0. hot ethanol extracts were analyzed via paper chromatography and autoradiography for products of co2 fixation. at 5 s, malate (51.5%) predominate ... | 1978 | 417691 |
| muscle sensitivity differences in two avian species to anatoxin-a produced by the freshwater cyanophyte anabaena flos-aquae nrc-44-1. | | 1978 | 417792 |
| pathways of assimilation of [13n]n2 and 13nh4+ by cyanobacteria with and without heterocysts. | the principal initial product of metabolism of [13n]n2 and 13nh4+ by five diverse cyanobacteria is glutamine. methionine sulfoximine inhibits formation of [13n]glutamine except in the case of gloeothece sp., an organism with a thick sheath through which the inhibitor may not penetrate. thus, glutamine synthetase appears to catalyze the initial step in the assimilation of n2-derived or exogenous nh4+ by these organisms. [13n]glutamate is, in all cases, the second major product of assimilation of ... | 1978 | 418057 |
| isolation and properties of fungi that lyse blue-green algae. | of 70 pure microbial cultures isolated from aquatic habitats, soil, and air according to the ability to lyse live blue-green algae, 62 were fungi representing the genera acremonium, emericellopsis, and verticillium. algal-lysing fungi were isolated from all habitat types sampled. the remaining isolates comprised four bacteria and four streptomycetes. all isolates lysed anabaena flos-aquae and, in most cases, several other filamentous and unicellular blue-green algae. the fungi generally showed g ... | 1978 | 418740 |
| sheep mortalities associated with the blue green alga nodularia spumigena. | in 2 field mortalities studied, sheep died and showed haemorrhage and diffuse liver necrosis after drinking water from dams containing growths of the blue green algae nodularia. sheep dosed with water containing n. spumigena mert 5, 9 and 18 days after collection from one of the farm dams developed pyrexia and leucopenia before death. at necropsy, these sheep showed extensive haemorrhage, accumulations of yellow fluid in body cavitis and acute hepatic necrosis. guinea pigs dosed with the water 9 ... | 1977 | 418760 |
| location of o-methyl sugars in antigenic (lipo-)polysaccharides of photosynthetic bacteria and cyanobacteria. | an attempt was made to localize a number of o-methyl sugars in lipopolysaccharides and antigenic polysaccharides isolated from photosynthetic bacteria and from cyano-bacteria. methylation analysis with [2h3]methyl iodide as methylating agent was the method of choice. one has to differentiate between (lipo-)polysaccharides having only trace amounts (less than 1% of polymer dry weight) of o-methyl sugars and those having them in larger amounts (more than 4% of polymer dry weight). in the former ca ... | 1978 | 418776 |
| evidence for the involvement of a genetic determinant controlling functional specificity of group vi b elements in the metabolism of n2 and no-3 in the blue-green alga nostoc muscorum. | | 1978 | 418780 |
| factors affecting energy transfer from phycobilisomes to thylakoids in anacystis nidulans. | short illumination with white light of dark-maintained anacystis nidulans prior to immersion in liquid nitrogen resulted in a marked change of fluorescence emission characteristics at 77 k. the fluorescence of photosystem ii-associated membrane bound pigments increases, while the emission due to phycobilins decreases. this effect seems to be due to a light-dependent alteration in the extent of contact between phycobilisomes and thylakoids, since the effect is reversible in the dark and is abolis ... | 1978 | 418809 |
| obligatory biosynthesis of l-tyrosine via the pretyrosine branchlet in coryneform bacteria. | species of coryneform bacteria (corynebacterium glutamicum, brevibacterium flavum, and b. ammoniagenes) utilize pretyrosine [beta-(1-carboxy-4-hydroxy-2,5-cyclohexadien-1-yl) alanine] as an intermediate in l-tyrosine biosynthesis. pretyrosine is formed from prephenate via the activity of at least one species of aromatic aminotransferase which is significantly greater with prephenate as substrate than with either phenylpyruvate or 4-hydroxyphenylpyruvate. pretyrosine dehydrogenase, capable of con ... | 1979 | 457594 |
| studies on plant bile pigments, vii. preparation and characterization of phycobiliproteins with chromophores chemically modified by reduction. | the reversible denaturation and reduction with dithionite has been studied for the phycobiliproteins, c-phycocyanin (1) and allophycocyanin (2) from spirulina platensis, and c-phycoerythrin (4) from fremyella diplosiphon (both cyanobacteria). by treatment with sodium dithionite, the chromophores are selectively reduced at the central (c-10) methine bridge, producing pigments with bilirubinoid (lambda max = 418 nm from 1 and 2), and vinylpyrroloc (lambda max= 300 nm from 4) chromophores. the exte ... | 1979 | 488917 |
| archean photoautotrophy: some alternatives and limits. | from the archean geological record, one can infer that photoautotrophy evolved early in earth history; however the nature of this photosynthesis -- whether it was predominately or cyanobacterial -- is less clearly understood. general agreement tht the earth's atmosphere did not become oxygen rich before the early proterozoic era places constraints on theories concerning more ancient biotas. accommodating this limitation in various ways, different workers have hypothesized (1) that blue-green alg ... | 1979 | 503457 |
| thermal pollution consequences of the implementation of the president's energy message on increased coal utilization. | the thermal consequences of coal utilization are most meaningfully assessed in comparison with the form of power generation replaced by coal which is most likely nuclear. the different effects are influenced by siting decisions and the intrinsic thermal efficiencies of the two fuel systems. nuclear power plants discharge 50% more waste rheat to the atmosphere through cooling towers or to a water body than coal-fired plants. coal-fired plants require about 2/3 as much water as nuclear power plant ... | 1979 | 540623 |
| porphyrins and phycobilins in precambrian rocks. | samples of precambrian rocks (1.7-2.6 billion years, u.s.s.r.) contain metalloporphyrins and linear tetrapyrrole pigment similar to phycobilin 655 from modern blue-green algae microystis (according to data of phosphorescence spectroscopy). the detection of ancient phycobilin makes it possible to relate the data on pigment paleobiochemistry with the evolution of photosynthetic system. | 1977 | 611431 |
| effects of low concentrations of bisulfite-sulfite and nitrite on microorganisms. | a wide range of microorganisms was tested to determine their sensitivity to low concentrations of bisulfite-sulfite and nitrite, solubility products of so2 and no2, respectively. photosynthesis by blue-green algae (cyanobacteria) was more strongly inhibited by 0.1 mm bisulfite-sulfite and 1 mm nitrite at ph 6.0 than photosynthesis by eucaryotic algae and respiration of bacteria, fungi, and protozoa. at ph 7.7, blue-green algae were still more sensitive to bisulfite-sulfite and nitrite than eucar ... | 1978 | 646357 |
| [base composition and dna content in single-cell cyanobacteria]. | the base composition and dna content were determined in 19 strains of cyanobacteria. the content of gc varied within the range of 33.6 to 70.7 mol%, and the content of dna, from 1.05 x 10(-14) to 28.7 x 10(-14) g per cell. the latter parameter almost directly depended on the cell volume. the cultures were subdivided into six groups according to the results obtained. | 1978 | 672685 |
| biliprotein assemble in the disc-shaped phycobilisomes of rhodella violacea. on the molecular composition of energy-transfering complexes (tripartite units) forming the periphery of the phycobilisome. | heterogeneous complexes with a molecular weight of about 790000 containing b-phycoerythrin (bangiales phycoerythrin) and c-phycocyanin (cyanophyceae phycocyanin) in a molar pigment ratio of 2:1 were isolated from purified, dissociated phycobilisomes. electron microscopical investigations revealed structures of three discs aggregated face to face with an apparent distance of 1.5 nm between each disc. two discs may represent phycoerythrin and one phycocyanin. the complexes are structurally identic ... | 1978 | 720347 |
| evolution of 5srna. | the evolution of 5srna of 17 organisms ranging from human to bacteria has been studied using a sequence homology analysis. the evolutionary rate of 5srna genes has been estimated to be 2.2x10(-10) replacement per one nucleotide site per year. this value is about the same as that of cytochrome c or trna's (congruent to 2x10(-10)). a phylogenic tree of these organisms including both eukaryotes and prokaryotes has been constructed from the evolutionary distances (the rate of nucleotide substitution ... | 1975 | 765486 |
| transfer of nitrogen-fixing (nif) genes in the blue-green alga nostoc muscorum. | | 1975 | 803368 |
| how homologous are the alpha and beta subunits of c-phycocyanin? | | 1975 | 803451 |
| amino acid sequence similarity between cytochrome f from a blue-green bacterium and algal chloroplasts. | | 1975 | 803642 |
| control of gene expression in blue-green algae. | | 1975 | 803643 |
| toxicology and pharmacological action of anabaena flos-aquae toxin. | calves, rats, ducks, and goldfish given lethal oral doses of bacteria-free lyophilized cell suspensions of toxic anabaena flos-aquae died as a result of respiratory arrest. experiments with selected animals and pharmacological preparations showed that the main effect of the toxin was production of a sustained postsynaptic depolarizing neuromuscular blockade. | 1975 | 803708 |
| 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 ... | 1975 | 803818 |
| 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 ... | 1975 | 803826 |
| the non-light-dependent reduction of 2,6-dichlorophenolindophenol by cells of the blue-green alga anacystis nidulans. | whole cells of the blue-green alga anacystis nidulans reduced, in the dark, the oxidation-reduction dye, 2,6-dichlorophenolindophenol at rates severalfold higher than those of the other algae tested. under anaerobiosis, the endogenous reductant was depleted after up to 80 nmol of dye were reduced per microliter of cells. cells held in darkness for several hours exhibited lowered dark reduction rates relative to cells held in light. treatment with lysozyme and ethylenediaminetetraacetic acid yiel ... | 1975 | 803864 |
| phosphate utilization and alkaline phosphatase activity in anacystis nidulans (synechococcus). | anacystis nidulans (synechococcus) was maintained in a medium of low phosphate concentration (0.1 mm) and grew with a normal doubling time of 5 hrs at 30 degrees c. such cultures had a normal pigment composition and alkaline phosphatase was detectable at low specific activities only. the onset of phosphate-limited growth occurred when the phosphate concentration in the medium fell to a value below 4 mum (the limit of accurate determination by the assay method used ) and resulted in increases in ... | 1975 | 804297 |
| subunits of phycoerythrin from fremyella diplosiphon: chemical and immunochemical characterization. | the alpha and beta subunits of the phycobiliprotein, phycoerythrin, isolated from the filamentous blue-green alga, fremyella diplosiphon, have been separated by chromatography on bio-rex 70 ion exchange resin. analysis by sodium dodecyl sulfate polyacrylamide gel electrophoresis shows no detectable cross-contamination of these subunit preparations. the molar extinction coefficients at 552 nm of the alpha and beta subunits in 8 m urea are 25,549 and 48,456, respectively. the amino acid compositio ... | 1975 | 804315 |
| [action spectra of photosynthesis and liberation of hydrogen in bacteria, algae and higher plants]. | | 1975 | 804393 |
| flash kinetics and light intensity dependence of oxygen evolution in the blue-green alga anacystis nidulans. | patterns of oxygen evolution in flashing light for the glue-green alga anacystis nidulans are compared with those for broken spinach chloroplasts and whole cells of the green alga chlorella pyrenoidosa. the oscillations of oxygen yield with flash number that occur in both anacystis and chlorella, display a greater degree of damping than do those of isolated spinach chloroplasts. the increase in damping results from a two- to threefold increase in the fraction (alpha) of reaction centers "misse ... | 1975 | 804933 |
| electron microscopic study of the infection of anacystis nidulans by the cyanophage as-1. | | 1975 | 805494 |
| photosynthetic studies with a 10-psec resolution streak camera. | | 1975 | 805592 |
| a simplified approach to studies of toxic toxaphene components. | | 1975 | 805615 |
| nitrogen fixation and the heterocyst in blue-green algae. | | 1975 | 805725 |
| nucleic acid synthesis and regulation in blue-green algae. | | 1975 | 805726 |
| dark-light transitions with a heterotrophic culture of a blue-green alga. | | 1975 | 805727 |
| phylogenetic origin of the chloroplast and prokaryotic nature of its ribosomal rna. | the 16s ribosomal rna of the euglena gracilis chloroplast has been characterized in terms of its two-dimensional electrophoretic "fingerprint" (t1 ribonuclease). results show it to be a typically prokaryotic 16 s rrna. by the present criterion, different chloroplasts are shown to be related to one another and at least distantly to blue-green algae and perhaps to bacillaceae. these results argue in favor of an endosymbiont origin of the chloroplast. | 1975 | 806081 |
| spectral properties of phycobilisomes and phycobiliproteins from the blue-green alga-nostoc sp. | | 1975 | 806082 |
| heat induction of the blue-green alga plectonema boryanum lysogenic for the cyanophage splcts1. | | 1975 | 806167 |
| the fine structure of the branched alpha-d-glucan from the blue-green alga anacystis nidulans: comparison with other bacterial glycogens and phytoglycogen. | the fine structure of the glycogen from the blue-green alga anacystis nidulans has been examined. after selective hydrolysis of all (1 yields 6)-alpha-d linkages by a bacterial isoamylase, the resulting mixture of linear chains was subjected to gel permeation chromatography. for purposes of comparison, the glycogens from escherichia coli and arthrobacter sp., amylopectin, phytoglycogen from sweet corn, and shell-fish glycogen were treated similarly. the profiles of the unit chains of a nidulans ... | 1975 | 806344 |
| amino acid sequence of spirulina platensis ferredoxin: a far divergency of blue-green algal ferredoxins. | | 1975 | 806473 |
| characterization of r-phycocyanin. chromophore content of r-phycocyanin and c-phycoerythrin. | r-phycocyanin was purified from two independent isolates of the unicellular red alga porphyridium cruentum. at ph 7.0 the protein sediments as a single component with s 20,w of 5.98 s (at 2 mg/ml, gamma/2=0.02). over a protein concentration range of 0.2 to 0.5 mg/ml (gamma/2=0.16), sedimentation equilibrium gave a molecular weight of 103,000 +/- 6,000 with no evidence of heterogeneity. in common with c-phydocyanins, r-phycocyanin consists of alpha and beta subunits of molecular weights of 18,200 ... | 1975 | 806593 |
| absence of repression in a phenylalanine auxotroph of synechococcus cedrorum. | | 1975 | 806657 |
| crystallographic characterization of flavodoxin from anacystis nidulans. | | 1975 | 806695 |
| mutants of anabaena cylindrica altered in heterocyst spacing. | nitrosoguanidine induced mutants of anabaena cylindrica have been obtained, which are altered in heterocyst spacing. in the wild type organism the pattern is composed of single intercalary heterocysts. the mutant patterns fall into several classes: those with only terminal heterocysts, with both terminal and intercalary heterocysts, with groups of heterocysts and those totally lacking heterocysts. the mutants are described in detail, and the various pattern modications are interpreted in terms ... | 1975 | 807173 |
| 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 ... | 1975 | 807175 |
| amino acid sequence of the spirulina maxima ferredoxin, a ferredoxin from a procaryote. | | 1975 | 807207 |
| structures of biogenic origin from early precambrian rocks of euro-asia. | spheroidal microfossils mainly 20 to 100 mug in diameter and exhibiting granular surface textures have been recovered from early precambrian rocks by applying a new method of water separation in combination with thin chemical preparation. in contrast to the acritarcha, these microfossils are characterized by a relatively low specific weight (close to one) and considerable fragility due to impregnation by mineral matter. they occur in archean sediments of hindustan, in rocks of the baltic and ald ... | 1975 | 807898 |
| basis for the resistance of several algae to microbial decomposition. | the basis for the resistance of certain algae to microbial decomposition in natural waters was investigated using pediastrum duplex, staurastrum sp., and fischerella muscicola as test organisms. enzyme preparations previously found to convert susceptible algae into spheroplasts had no such effect on the resistant species, although glucose and galacturonic acid was released from p. duplex walls. little protein or lipid but considerable carbohydrate was found in the walls of the refractory organis ... | 1975 | 808166 |
| effect of pesticides on blue-green algae and nitrogen-fixation. | the effects of the pesticides, amitrol, a derivative of amitrol (viz. 3,5-diamino-1,2,4-triazole), diquat, paraquat, linuron, mcpa, malathion, and monuron, were studied on the nitrogen-fixing algae, anabaena cylindrica, aulosira sp., calothrix elenkenii. chlorogloeae frischii, cylindrospermum muscicola, nostoc sp. from collema tenax, nostoc muscorum tolypothrix tenuis, and westiellopsis sp. in general, two types of response were discernible; an initial period of depression succeeded by an increa ... | 1975 | 808179 |
| the control of carbon dioxide assimilation and ribulose 1,5-diphosphate carboxylase activity in anacystis nidulans grown in a light-limited chemostat. | the blue-green alga, anacystis nidulans, was grown in a light-limited chemostat at specific growth rates ranging from 0.02 h-1 to 0.10h-1. the rate of carbon dioxide assimilation, measured under optimal experimental conditions, increased 3 to 5 fold with increasing growth rate over this range. ribulose 1,5-diphosphate carboxylase (rudpcase) activity per organism increased four fold over the same growth rate range. rudpcase specific activity in terms of total protein remained constant at all grow ... | 1975 | 808184 |
| the effect of inhibitors on the electron flow triggering photo-phobic reactions in cyanophyceae. | 1. since photo-phobic reactions in the blue green alga phormidium uncinatum seem to be triggered by changes of electron flow rates into or out of an electron pool situated in the electron transport chain between photo-system ii and i, the effect of inhibitors affecting the electron transport chain has been studied. 2. dose response curves of the phobic reaction have been measured by varying the trap energy in double beam light trap experiments with constant pairs of monochromatic light. from the ... | 1975 | 808185 |
| allophycocyanin b (lambdamax 671, 618 nm): a new cyanobacterial phycobiliprotein. | a hitherto undescribed red fluorescent phycobiliprotein (maximum emission at congruent to 680 nm), characterized by long wavelength absorption maxima in the visible region at 671 nm (xi = 172000 m(-1).cm(-1) per monomer of mol. wt. 30600)and 618 nm, has been purified to homogeneity from unicellular cyanobacterium, synechococcus sp., and from a filamentous cyanobacterium, anabaena variabilis. the name allophycocyanin b has been proposed for the new protein. a. variabilis allophycocyanin b is ch ... | 1975 | 808186 |
| requirement of low oxidation-reduction potential for photosynthesis in a blue-green alga (phormidium sp.). | photosynthesis in a phormidium species which forms dense conical-shaped structures in thermal springs is strongly inhibited by aeration but is stimulated by sulfide and other agents (cysteine, thioglycolate, sulfite) which lower the oxidation-reduction potential. the compact structures which this alga forms in nature may restrict oxygen penetration from the enviroment so that the anaerobic or microaerophilic conditions necessary ofr photosynthesis can develop. the alga may be defective in a re ... | 1975 | 808187 |
| a survey of available nitrogen sources for growth of the blue-green alga, agmenellum quadruplicatum. | the growth response of the marine blue-green alga, agmenellum quadruplicatum to 60 inorganic and organic nitrogen sources was studied. these compounds were offered as sole nitrogen sources. most amino acids, most purines, and urea were good nitrogen sources for growth. | 1975 | 808189 |
| rna synthesis and the accumulation of guanine nucleotides during growth shift down in the blue-green alga anacystis nidulans. | shift down of growth rate in the blue-green alga anacystis nidulans by reduction of the incident light intensity produced a reduction in the rate of stable rna accumulation which was correlated with increased concentrations of three phosphorylated compounds, two of which were identified as guanosine 5'-diphosphate-3'-diphosphate (ppgpp) and guanosine 5'-triphosphate3'-diphosphate (pppgpp). the step also causes a large but transient increase in the concentration of gtp. stable rna fails to accumu ... | 1975 | 808240 |