| ultraviolet and osmotic stresses induce and regulate the synthesis of mycosporines in the cyanobacterium chlorogloeopsis pcc 6912 | the cyanobacterium chlorogloeopsis pcc 6912 was found to synthesize and accumulate two putative uv sunscreen compounds of the mycosporine (mycosporine-like amino acid; maa) type: mycosporine-glycine and shinorine. these maas were not constitutively present in the cells; their synthesis could be induced specifically either by exposure to uvb radiation (280-320 nm) or by osmotic stress, but not by other stress factors such as heat or cold shock, nutrient limitation, or photooxidative stress. a sig ... | 1999 | 10525734 |
| insertion sequence is2 in the cyanobacterium chlorogloeopsis fritschii. | a cloned dna fragment, previously demonstrated to encode ribulose bisphosphate carboxylase/oxygenase (rubisco) of chlorogloeopsis fritschii strain ccap1411/1b, is shown also to include the entire transposable element, is2, normally a resident in the escherichia coli genome. southern-blot hybridisation experiments confirm the presence of is2 in the c. fritschii genome. this finding adds a new and unrelated species to the known host range of this element and provides evidence of genetic transfer b ... | 1988 | 2844631 |
| evidence for an ultraviolet sunscreen role of the extracellular pigment scytonemin in the terrestrial cyanobacterium chlorogloeopsis sp. | the proposed photoprotective role of the uv-a absorbing, extracellular pigment scytonemin was studied in the terrestrial cyanobacterium chlorogloeopsis sp. strain o-89-cgs(1). uv-a (315-400 nm) caused growth delay, cell growth restarting only when scytonemin had accumulated in the extracellular envelopes. cultures with scytonemin were more resistant to photoinhibition of photosynthesis than cultures without scytonemin, the differential resistance being much greater to uv-a-caused photoinhibition ... | 1992 | 1508978 |
| expression of a gene encoding a novel ferredoxin in the cyanobacterium synechococcus 6301. | a gene was discovered in the cyanobacterium synechococcus 6301 that encodes a protein highly related to members of the [2fe-2s] ferredoxin family found in chloroplasts and cyanobacteria. it follows a cluster of seven genes encoding subunits of the cyanobacterial atp synthase complex. it is transcribed as a monocistronic mrna of 408 nucleotide residues. transcription starts at a site 55 bp upstream of the initiator methionine codon. transcriptional initiation and termination signals with sequence ... | 1988 | 2843173 |
| amino acid sequences of nostoc strain mac ferredoxins i and ii. | the amino acid sequences of ferredoxins i and ii from a blue-green alga, nostoc strain mac were determined. this alga is able to grow autotrophically in the light or heterotrophically in the dark. analyses of tryptic peptides of cm-proteins by conventional methods including solid-phase edman degradation gave the complete amino acid sequences. both molecules consisted of 98 amino acid residues and 34 amino acid differences including two deletions were found between the two. comparing these sequen ... | 1982 | 6818220 |
| efficiency of ferredoxins and flavodoxins as mediators in systems for hydrogen evolution. | 1. the efficiencies of ferredoxins and flavodoxins from a range of sources as mediators in systems for hydrogen evolution were assessed. 2. in supporting electron transfer from dithionite to hydrogenase of the bacterium clostridium pasteurianum, highest activity was shown by the ferredoxin from the cyanobacterium chlorogloeopsis fritschii and flavodoxin from the bacterium megasphaera elsdenii. the latter was some twenty times as active as comparable concentrations of methyl viologen. ferredoxins ... | 1980 | 7016115 |
| glucose dehydrogenase of chlorogloeopsis fritschii. | | 1975 | 236958 |
| characteristic fragmentation of bacteriohopanepolyols during atmospheric pressure chemical ionisation liquid chromatography/ion trap mass spectrometry. | bacteriohopanepolyols (bhps) fragment via characteristic pathways during atmospheric pressure chemical ionisation liquid chromatography/ion trap mass spectrometry (apci-lc/ms(n)). comparison of the ms(2) spectra of bacteriohopane-32,33,34,35-tetrol (bht) and 2 beta-methylbacteriohopane-32,33,34,35-tetrol has confirmed the previously proposed ring-c cleavage occurring between c-9 and 11 and c-8 and 14. this fragmentation, diagnostic of all hopanoids, also occurs in bhps containing an amino group ... | 2003 | 14673828 |
| polyphyly of true branching cyanobacteria (stigonematales). | cyanobacteria with true branching are classified in subsection v (formerly order stigonematales) in the phylum cyanobacteria: they exhibit a high degree of morphological complexity and are known from particular biotopes. only a few stigonematalean morphotypes have been cultured, and therefore the high variability of morphotypes found in nature is under-represented in culture. axenic cultures of chlorogloeopsis and fischerella sensu rippka et al. were, to date, the only representatives of this su ... | 2004 | 15023942 |
| effects of carbon nutrition on the physiological expression of hco3- transport and the co2-concentrating mechanism in the cyanobacterium chlorogloeopsis sp. atcc 27193. | we have examined the effect of inorganic and organic carbon nutrition on the physiological expression of hco3- transport and the co2-concentrating mechanism (ccm) in the nutritionally versatile cyanobacterium chlorogloeopsis sp. atcc 27193. cells grown under photoautotrophic conditions in the presence of limiting or replete levels of inorganic carbon (ci), or grown under mixotrophic (light) or chemoheterotrophic (dark) conditions in the presence of sucrose retained both active co2 and na(+)-inde ... | 2002 | 11926192 |
| boron requirement in cyanobacteria : its possible role in the early evolution of photosynthetic organisms. | the effect of boron on heterocystous and nonheterocystous dinitrogen fixing cyanobacteria was examined. the absence of boron in culture media inhibited growth and nitrogenase activity in nodularia sp., chlorogloeopsis sp., and nostoc sp. cultures. examinations of boron-deficient cultures showed changes in heterocyst morphology. however, cultures of nonheterocystous cyanobacteria, gloeothece sp. and plectonema sp., grown in the absence of boron did not show any alteration in growth or nitrogenase ... | 1990 | 16667889 |
| heterocyst-forming filamentous cyanobacteria encode proteins that resemble eukaryotic rna-binding proteins of the rnp family. | heterocyst-forming cyanobacteria have multiple genes encoding proteins that are similar to the rnp family of eukaryotic rna-binding proteins. three genes from two strains of cyanobacteria (anabaena and chlorogloeopsis) have been sequenced. all three putative gene products contain a single rna recognition motif (rrm) that includes the highly conserved rnp1 and rnp2 regions and all three have an auxiliary motif consisting either of a short glycine-rich carboxy-terminal tail or a carboxy-terminal t ... | 1994 | 8289320 |
| amino acid sequence of chlorogloeopsis fritschii ferredoxin: taxonomic and evolutionary aspects. | the amino acid sequence of chlorogloeopsis fritschii ferredoxin was determined for its carboxymethylated derivative by using solid-phase sequencing, fragmentation with various enzymes, and manual edman degradation procedures. the ferredoxin was composed of 98 amino acid residues and lacked methionine and tryptophan. the sequence was as follows: ala-thr-tyr-lys-val-thr-leu-ile-asn-asp-ala-glu- gly-leu-asn-gln-thr-ile-glu-val-asp-asp-asp-thr-tyr-ile-leu-asp-ala-ala-glu- glu-ala-gly-leu-asp-leu-pro ... | 1982 | 6818222 |
| multiple evidence for widespread and general occurrence of type-iii pha synthases in cyanobacteria and molecular characterization of the pha synthases from two thermophilic cyanobacteria: chlorogloeopsis fritschii pcc 6912 and synechococcus sp. strain ma19. | eleven different cyanobacteria were investigated with respect to their capabilities to synthesize poly-3-hydroxybutyrate [poly(3hb)] and the type of poly-beta-hydroxyalkanoic acid (pha) synthase accounting for the synthesis of this polyester. several methods, including (i) southern blot analysis using a phac-specific dna probe, (ii) western blot analysis using specific polyclonal anti-phae antibodies raised in this study against phae of synechocystis sp. strain pcc 6803, (iii) generation and seq ... | 2001 | 11700355 |
| a novel prokaryotic uvb photoreceptor in the cyanobacterium chlorogloeopsis pcc 6912. | we present evidence for the presence and nature of a uvb-specific photoreceptor in the cyanobacterium chlorogloeopsis pcc 6912. the photoreceptor mediates at least the photosensory induction of mycosporine-like amino acid (maa) synthesis. because maa synthesis in this organism can also be induced under salt stress, we could distinguish between the photosensory and the purely biochemical requirements of maa synthesis. neither visible light nor uv radiation was necessary for the biosynthetic proce ... | 2000 | 10824604 |
| a comparative genomics approach to understanding the biosynthesis of the sunscreen scytonemin in cyanobacteria. | the extracellular sunscreen scytonemin is the most common and widespread indole-alkaloid among cyanobacteria. previous research using the cyanobacterium nostoc punctiforme atcc 29133 revealed a unique 18-gene cluster (npr1276 to npr1259 in the n. punctiforme genome) involved in the biosynthesis of scytonemin. we provide further genomic characterization of these genes in n. punctiforme and extend it to homologous regions in other cyanobacteria. | 2009 | 19630972 |
| phenotypic and genotypic comparison of symbiotic and free-living cyanobacteria from a single field site. | pcr amplification techniques were used to compare cyanobacterial symbionts from a cyanobacterium-bryophyte symbiosis and free-living cyanobacteria from the same field site. thirty-one symbiotic cyanobacteria were isolated from the hornwort phaeoceros sp. at several closely spaced locations, and 40 free-living cyanobacteria were isolated from the immediate vicinity of the same plants. one of the symbiotic isolates was a species of calothrix, a genus not previously known to form bryophyte symbiose ... | 1997 | 16535734 |
| [the accumulation and degradation dynamics of cyanophycin in cyanobacteria grown in symbiotic associations with plant tissues and cells]. | five different artificial associations of cyanobacterial cells with the cells or tissues of nightshade and rauwolfia were studied. the associations grown on nitrogen-containing media produced heterocysts. cyanobacterial cells in the associations retained their ability to take up bound nitrogen from the medium, to store it in the form of cyanophycin granules, and to use them in the process of symbiotic growth. the synthesis and degradation of cyanophycin granules in cyanobacterial cells were more ... | 2003 | 12901011 |
| structure of the 16 s ribosomal rna of the thermophilic cyanobacterium chlorogloeopsis htf ('mastigocladus laminosus htf') strain pcc7518, and phylogenetic analysis. | the thermophilic cyanobacterial strain, pcc7518, originally identified as 'mastigocladus laminosus htf' does not show branchings or heterocysts. the absence of branchings supports the later assignment to the genus chlorogloeopsis. the absence of heterocysts may be the result of a mutation because heterocysts were observed in the original isolate. alternatively, contamination may have happened. to solve this problem, the 16 s rrna sequence was determined and used to infer a secondary structure mo ... | 1993 | 8428640 |