| photosystem ii regulation of macromolecule synthesis in the blue-green alga aphanocapsa 6714. | polymers synthesized by heterotrophically growing (glucose as carbon source) cultures of aphanocapsa 6714 were compared with polymers synthesized in photosynthetically grown cultures. loss of photosystem ii by dark incubation, or inhibition of light-grown cells with the photosystem ii-specific inhibitor dichlorophenylmethylurea, caused an 80 to 90% reduction in the rate of lipid and total ribonucleic acid synthesis, and more than a 90% reduction in the rate of protein synthesis. in contrast, gl ... | 1976 | 10279 |
| acetate uptake by the unicellular cyanobacteria synechococcus and aphanocapsa. | | 1977 | 18124 |
| carbon dioxide assimilation in cyanobacteria: regulation of ribulose, 1,5-bisphosphate carboxylase. | cyanobacteria assimilate carbon dioxide through the calvin cycle and therefore must regulate the activity of ribulose 1,5-bisophosphate carboxylase. using an in situ assay, as well as measuring the activity in crude, partially purified, and homogeneous preparations, we can show that a number of phosphorylated intermediates exert a regulatory role. three diverse organisms, agmenellum quadruplicatum, aphanocapsa 6714, and anabaena sp. ca, were studied, and it was found that the in situ and cell-fr ... | 1979 | 40958 |
| arginine catabolism in aphanocapsa 6308. | the catabolic products of arginine metabolism were observed in aphanocapsa 6308, a unicellular cyanobacterium, by thin layer chromatography of growth media, by limiting growth conditions, and by enzymatic analysis. of the organic, nitrogenous compounds examined, only arginine supported growth in co2-free media. the excretion of ornithine at a concentration level greater than citrulline suggested the existence in aphanocapsa 6308 of the arginine dihydrolase pathway which produced ornithine, co2,n ... | 1978 | 100070 |
| kinetics of light-dark co2 fixation and glucose assimilation by aphanocapsa 6714. | cells of aphanocapsa 6714 were subjected to alternating ligh-dark periods (flashing-light experiments). the corresponding activation (in the light) and inactivation (in the dark) of the reductive pentose cycle was measured, in vivo, from initial rates of 14co2 incorporation and also by changes in the total concentration of 14c and 32p in soluble metabolites. two principle sites of metabolic regulation were detected: (i) co2 fixation was inactivated 15 to 20 s after removal of the light source, b ... | 1976 | 185198 |
| 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 |
| 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 |
| direct measurement of pure absorbance spectra of living phototrophic microorganisms. | the pure absorbance of turbid cell suspensions of various phototrophic microorganisms were determined by collecting the scattered light. a conventional spectrophotometer was used, equipped with an intergrating sphere as receiver unit, which allowed precise measurements of the absorbance in the range from zero to 0.1. in the wavelength range 300--1100 nm, where photosynthesis occurs, light scattered only once by a bacterial cell retains predominantly the forward direction. this allows measurement ... | 1978 | 626755 |
| 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 |
| nonribosomal nature of novel, stable ribonucleic acid species accumulated by blue-green bacteria. | the facultatively chemoheterotrophic blue-green bacterium aphanocapsa 6714 accumulates two novel, stable ribonucleic acid species when deprived of sources of carbon and energy. at least one of these species is nonribosomal. | 1976 | 816786 |
| [a genetic transfer system in a cyanophyte of the genus aphanocapsa]. | the possibility of a genetic transfer, through a process of transformation, has been shown in a unicellular, facultative chemoheterotroph blue-green algae, aphanocapsa 6714. similarly to the process described with anacystis nidulans, the recipient strain becomes competent when the growth reaches its second, slower, exponential phase. the genetic marker conferring resistance to p-f-phenylalanine has been transferred with a frequency 20 to 100 times higher than that of the spontaneous mutations. t ... | 1976 | 817846 |
| cyanobacterial dna-binding protein related to escherichia coli hu. | a dna-binding protein has been isolated from two cyanobacteria (blue-green algae): anabaena sp and aphanocapsa sp. it has a molecular weight as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis of about 10,000, is rich in lysine and arginine, and lacks tyrosine, tryptophan, and cysteine. the proteins from both strains show immunological identity with a similar dna-binding protein from escherichia coli, when tested by immunodiffusion with an antiserum prepared against the e. ... | 1976 | 819928 |
| cloning and nucleotide sequence of the crti gene encoding phytoene dehydrogenase from the cyanobacterium aphanocapsa pcc6714. | the membrane-bound phytoene dehydrogenase (pd) is an enzyme in carotenoid biosynthesis which is essential in all microorganisms and plants containing these colored pigments. despite its key role in the regulation of carotenogenesis, the biochemistry and molecular biology of pd are poorly understood. we have cloned, sequenced and expressed a portion of the pd-encoding gene, crti, from the blue-green algae aphanocapsa pcc6714. the gene codes for a 532-amino acids (aa) protein, with a calculated mr ... | 1990 | 2119326 |
| immunological detection of phytoene desaturase in algae and higher plants using an antiserum raised against a bacterial fusion-gene construct. | immunological characterization of phytoene desaturase, a key enzyme of carotenoid biosynthesis, is reported. for this purpose, a phytoene-desaturase fusion protein has been employed. for its construction 921 base pairs of the crti gene were fused to the n-terminal region of the escherichia coli lacz gene. plasmid pgabx2 resulted from insertion of a bgli - xhoi fragment from the rhodobacter capsulatus carotenoid biosynthesis gene cluster, carrying the crti, crta and crtb genes, into pbr322. a 968 ... | 1989 | 2676534 |
| immunological characterization of photosystem ii chlorophyll-binding proteins from the cyanobacterium, aphanocapsa 6714. | chlorophyll-binding proteins from the cyanobacterium aphanocapsa 6714 were identified by immunoblotting procedures. three chlorophyll-binding complexes, cpiii', cpiiia, and cpiiib, were associated with psii. cpiii' likely serves as an' antenna to psii in aphanocapsa since it could be removed from active psii core preparations without loss of activity. the cpiii' proteins cross-reacted to antibodies prepared against the maize psii light-harvesting complex, lhc-ii. the cpiiia polypeptides cross-re ... | 1986 | 3091588 |
| 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 |
| efficiency of energy conversion by aerobic glucose metabolism in aphancapsa 6714. | efficiency of adenosine triphosphate (atp) formation from glucose oxidation in aphanocapsa 6714 was estimated by quantitative measurement of phosphorylated intermediary metabolites and glycogen (polyglucose) formed from (14)c-glucose. p/2e ratios based on oxygen uptake ranged from 2.62 to 3.08, whereas those based on (14)co(2) evolution ranged from 1.66 to 1.72. the synthesis of glycogen, which is the dominant energy-consuming process in resting cells exposed to exogenous glucose, was almost tot ... | 1973 | 4199518 |
| kinetics of glucose incorporation by aphanocapsa 6714. | photoautotrophic metabolism of co(2) was compared with glucose metabolism in the facultative unicellular blue-green alga, aphanocapsa 6714. glucose-fed cells incorporated more (14)c into phosphorylated sugar intermediates of the reductive and oxidative pentose phosphate cycles than autotrophic cells. the relative increases were: 140-fold in dark cells; 32-fold in dichlorophenylmethylurea (dcmu)-inhibited cells; and 16-fold in cells assumilating glucose during photosynthetic carbon reduction. on ... | 1973 | 4199519 |
| fatty acid composition of unicellular strains of blue-green algae. | the fatty acids of 34 strains of unicellular blue-green algae provisionally assigned to the genera synechococcus, aphanocapsa, gloeocapsa, microcystis, and chlorogloea by stanier et al. have been chemically characterized. the strains analyzed can be divided into a series of compositional groups based upon the highest degree of unsaturation of the major cellular fatty acids. twenty strains fall into the group characterized by one trienoic fatty acid isomer (alpha-linolenic acid), and seven strain ... | 1972 | 4621688 |
| light inhibition of respiration is due to a dual function of the cytochrome b6-f complex and the plastocyanin/cytochrome c-553 pool in aphanocapsa. | studies of the respiratory electron transport pathway in the blue-green alga, aphanocapsa, demonstrated the presence of cytochrome oxidase and a cytochrome complex. the use of antimycin a showed only the occurrence of a plastidal type of cytochrome complex (the cytochrome b6-f complex), which is insensitive to this inhibitor. determination of the extent of photooxidation of cytochromes c-553 and f-556 under conditions of high and low cytochrome oxidase activities indicated an electron flow throu ... | 1984 | 6091561 |
| protein degradation and synthesis of cyanophycin granule polypeptide in aphanocapsa sp. | cyanophycin granule polypeptide content increased by 2- to 3-fold, soluble protein content decreased by 1.5-fold, and carbohydrate content increased by 2-fold within 6 h of chloramphenicol addition to exponentially growing cells of aphanocapsa sp. strain 6308. analysis of 14c- and 3h-labeled cells transferred to unlabeled medium and analysis of pulse-labeled cells both suggested cyanophycin granule synthesis from preformed protein breakdown. | 1983 | 6406434 |
| cyanophycin granule polypeptide formation and degradation in the cyanobacterium aphanocapsa 6308. | the effect of a number of conditions on the amount of cyanophycin granule polypeptide [multi-l-arginyl poly(l-aspartic acid)] formed in the unicellular cyanobacterium aphanocapsa 6308 was determined. light, co2, sulfur, and phosphorus starvation as well as the addition of arginine to culture media increased the amount of cyanophycin granule polypeptide in cells when compared with that in cells grown under conditions optimal for growth. nitrogen limitation and reduction of growth temperature to 3 ... | 1980 | 6767688 |
| structure and composition of cyanophycin granules in the cyanobacterium aphanocapsa 6308. | cyanophycin granules in the unicellular cyanobacterium aphanocapsa 6308 were examined with the electron microscope in both thin section and by freeze-fracture techniques. purified granules were examined with the electron microscope, by arginine determinations, by chromatography, and by elemental analysis. they are similar in ultrastructure and composition to those isolated from the nitrogen-fixing cyanobacterium anabaena cylindrica, consisting of equal molar quantities of l-arginine and l-aspart ... | 1980 | 6767696 |
| 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. ... | 2001 | 11759698 |
| cyanobacteria associated with anopheles albimanus (diptera: culicidae) larval habitats in southern mexico. | cyanobacteria associated with anopheles albimanus wiedemann larval habitats from southern chiapas, mexico, were isolated and identified from water samples and larval midguts using selective medium bg-11. larval breeding sites were classified according to their hydrology and dominant vegetation. cyanobacteria isolated in water samples were recorded and analyzed according to hydrological and vegetation habitat breeding types, and mosquito larval abundance. in total, 19 cyanobacteria species were i ... | 2002 | 12495179 |
| the biogeography and phylogeny of unicellular cyanobacterial symbionts in sponges from australia and the mediterranean. | the distribution, host associations, and phylogenetic relationships of the unicellular cyanobacterial symbionts of selected marine sponges were investigated with direct 16s rdna sequencing. the results indicate that the symbionts of the marine sponges aplysina aerophoba, ircinia variabilis, and petrosia ficiformis from the mediterranean, four chondrilla species from australia and the mediterranean, and haliclona sp. from australia support a diversity of symbionts comprising at least four closely ... | 2004 | 15546037 |
| cyanobacteria and prawn farming in northern new south wales, australia--a case study on cyanobacteria diversity and hepatotoxin bioaccumulation. | harmful cyanobacteria pose a hazard to aquatic ecosystems due to toxins (hepatotoxic microcystins, nodularins, and cylindrospermopsin) they produce. the microcystins and nodularins are potent toxins, which are also tumor promoters. the microcystins and nodularins may accumulate into aquatic organisms and be transferred to higher trophic levels, and eventually affect vector animals and consumers. prawn farming is a rapidly growing industry in australia. because information regarding effects of cy ... | 2005 | 15737678 |
| populations of exopolysaccharide-producing cyanobacteria and diatoms in the mucilaginous benthic aggregates of the tyrrhenian sea (tuscan archipelago). | the microalgal community of benthic mucilages sampled in various sites of the tuscan archipelago during the period may 1999-july 2002, was always dominated by diatoms. synedra, licmophora and navicula were the most frequently found genera, their presence having been observed within all the period under study; other ten genera of diatoms were found in the benthic mucilages, but their presence was dependent on the month and the year of observation. as concerns the cyanobacterial community, the fil ... | 2005 | 16271382 |
| feeding characteristics of an amoeba (lobosea: naegleria) grazing upon cyanobacteria: food selection, ingestion and digestion progress. | bacterivory by heterotrophic nanoflagellates and ciliates has been widely studied in aquatic environments, but data on the grazing of amoebae, are still scarce. from the water samples of dianchi lake (kunming, yunnan province, china), we isolated an amoeba, designated as naegleria sp. strain w2, which had potent grazing effects on some kind of cyanobacteria. the food selection mechanism and the digestion process of the amoeba were investigated in batch experiments. predation experiments showed t ... | 2006 | 16598635 |
| contributions of respiratory and photosynthetic pathways during growth of a facultative photoautotrophic cyanobacterium, aphanocapsa 6714. | comparison of the growth parameters and photosynthetic capacities of cells of aphanocapsa 6714 under various growth conditions led to the following conclusions: (a), no enzymic regulation of co(2)/glucose assimilation takes place in this strain; (b), functioning of photodependent phosphorylating pathways turns off oxidative atp synthesis; (c), no efficient regulation of pigment synthesis exists in these cells; (d), most modulations of photosynthetic activities probably occur through structural m ... | 1981 | 16662036 |
| effects of photosystem ii herbicides on the photosynthetic membranes of the cyanobacterium aphanocapsa 6308. | the effects of the photosystem ii herbicides diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea) and atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) on the photosynthetic membranes of a cyanobacterium, aphanocapsa 6308, were compared to the effects on a higher plant, spinacia oleracea. the inhibition of photosystem ii electron transport by these herbicides was investigated by measuring the photoreduction of the dye 2,6-dichlorophenol-indophenol spectrophotometrically using isolated mem ... | 1983 | 16662835 |
| stromal acidification mediates in vivo water stress inhibition of nonstomatal-controlled photosynthesis. | stromal acidification has been reported to mediate reduced osmotic potential (psi(pi)) effects on photosynthesis in the isolated spinach chloroplast (berkowitz, gibbs 1983 plant physiol 72: 1100-1109). to determine if stromal acidification mediates osmotic dehydration inhibition of photosynthesis in vivo, the effects of a weak base (nh(4)cl), which raises stromal ph, on co(2) fixation of vacuum-infiltrated spinach leaf slices, chlamydomonas reinhardii cells and aphanocapsa 6308 cells under isoto ... | 1983 | 16663131 |
| iron-sulfur centers and activities of the photosynthetic electron transport chain in iron-deficient cultures of the blue-green alga aphanocapsa. | cultures of the blue-green alga, aphanocapsa, were grown under iron-limiting conditions and changes in concentration of redox components of the photosynthetic electron transport chain, particularly iron-sulfur centers, were monitored by spectroscopic methods. a moderate iron depletion (1/10 of the normal concentration) had little effect on photosynthetic electron transport reactions and growth. nevertheless, the amount of membrane-bound non-heme iron decreased sharply, and ferredoxin was nearly ... | 1983 | 16663290 |
| screening and selection of most potent diazotrophic cyanobacterial isolate exhibiting natural tolerance to rice field herbicides for exploitation as biofertilizer. | periodic applications of heavy dosages of herbicides in modern rice-agriculture are a necessary evil for obtaining high crop productivity. such herbicides are not only detrimental to weeds but biofertilizer strains of diazotrophic cyanobacteria also. it is therefore, essential to screen and select such biofertilizer strains of diazotrophic cyanobacteria exhibiting natural tolerance to common rice-field herbicides that can be further improved by mutational techniques to make biofertilizer technol ... | 2006 | 16721882 |
| cyanopeptoline cb071: a cyclic depsipeptide isolated from the freshwater cyanobacterium aphanocapsa sp. | cyanopeptolin cb071 (1), a trypsin inhibitor, was isolated from the freshwater cyanobacterium aphanocapsa sp. its complete structure was determined by detailed nmr spectroscopy and ms analyses, along with chemical reactions. the compound showed inhibition of trypsin at a concentration of ic50=2.5 microm. | 2008 | 18670126 |
| a hypersaline microbial mat from the pacific atoll kiritimati: insights into composition and carbon fixation using biomarker analyses and a 13c-labeling approach. | modern microbial mats are widely recognized as useful analogs for the study of biogeochemical processes relevant to paleoenvironmental reconstruction in the precambrian. we combined microscopic observations and investigations of biomarker composition to investigate community structure and function in the upper layers of a thick phototrophic microbial mat system from a hypersaline lake on kiritimati (christmas island) in the northern line islands, republic of kiribati. in particular, an explorato ... | 2009 | 19476506 |
| driving factors of the phytoplankton functional groups in a deep mediterranean reservoir. | the control of phytoplankton growth is mainly related to the availability of light and nutrients. both may select phytoplankton species, but only if they occur in limiting amounts. during the last decade, the functional groups approach, based on the physiological, morphological and ecological attributes of the species, has proved to be a more efficient way to analyze seasonal changes in phytoplankton biomass. we analysed the dynamics of the phytoplankton functional groups sensu reynolds, recogni ... | 2010 | 20398914 |
| association between biotic and abiotic parameters and the occurrence of cyanobacteria in a brazilian reservoir. | the water reservoir of vargem das flores, brazil, has been subject to eutrophication problems. the occurrence of cyanobacterial blooms in this water body has raised concerns regarding the presence of toxic metabolites. in order to understand the factors that promote the proliferation and distribution of cyanobacteria in the reservoir, physicochemical parameters, species composition, and toxicity of the reservoir water column were analyzed at monthly intervals over a 3-year period (2004-2007) usi ... | 2011 | 21887480 |