| the cyanobacteriales: a legitimate order based on the type strain cyanobacterium stanieri? | as a logical consequence of the definition of a bacterium (stanier and van niel, 1962), r. y. stanier created the name "cyanobacteria" as a replacement for "blue-green algae". as such, cyanobacteria entered the 8th issue of bergey's manual of determinative bacteriology 1974 as members of the procaryotae murray 1968, this kingdom being composed of two divisions, cyanobacteria and bacteria. an even tighter integration of cyanobacteria with other bacteria was proposed by gibbons and murray (1978) f ... | 1983 | 6416126 |
| distribution of rubisco genotypes along a redox gradient in mono lake, california. | partial sequences of ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) (ec 4.1.1.39) genes were retrieved from samples taken along a redox gradient in alkaline, hypersaline mono lake, calif. the form i gene (cbbl) was found in all samples, whereas form ii (cbbm) was not retrieved from any of the samples. none of the rubisco sequences we obtained were closely related (nucleotide similarity, <90%) to sequences in the database. some could be attributed to organisms isolated from the lake (c ... | 2004 | 15184142 |
| toxic microcystis is widespread in lake erie: pcr detection of toxin genes and molecular characterization of associated cyanobacterial communities. | during the past decade, algae blooms, which include the toxic cyanobacterium microcystis, have reoccurred in the laurentian great lakes, most commonly in the western basin of lake erie. whereas the western basin is the most impacted by toxic microcystis in lake erie, there has historically been little effort focused on identifying the spatial distribution of microcystis throughout this lake. to address this lack of knowledge, we have employed a polymerase-chain-reaction-based detection of genes ... | 2006 | 16435169 |
| impact of 17alpha-ethinylestradiol on the plankton in freshwater microcosms--ii: responses of phytoplankton and the interrelation within the ecosystem. | effects of 17alpha-ethinylestradiol (ee) on phytoplankton were investigated in a lentic freshwater microcosm study. treatment with ee caused a shift in the species composition as shown by a principle response curve. whereas densities of cyanophyceae, dinophyceae, and chrysophyceae increased, those of conjugatophyceae and cryptophyceae decreased. furthermore, relative density of chlorophyceae declined after ee treatment. the changes showed taxa-specific time dependencies. some species, especially ... | 2008 | 17391760 |
| picocyanobacterial community structure of freshwater lakes and the baltic sea revealed by phylogenetic analyses and clade-specific quantitative pcr. | phylogenetic relationships among picocyanobacteria from the syn/pro clade sensu sánchez-baracaldo et al. (2005) were determined using small subunit (ssu) rdna sequences from novel culture isolates together with environmental samples from the baltic sea and seven freshwater lakes. the picocyanobacterial community comprised members of previously identified clades and of two previously undescribed clades. the number of well-supported clades suggests that freshwater picocyanobacterial communities en ... | 2008 | 18957588 |
| diversity of hepatotoxic cyanobacteria in the nile delta, egypt. | optimized denaturing gradient gel electrophoresis (dgge) fingerprinting and real-time pcr were performed to identify and quantify the potential hepatotoxic microcystin- and nodularin-producing cyanobacteria present in freshwater samples collected during different seasons at three different sites from the nile river delta. the combined use of molecular gene markers (targeting the aminotransferase domain of the hepatotoxin synthetase modules and the 16s rrna gene) and light microscopy demonstrated ... | 2009 | 19137148 |
| distinct patterns of picocyanobacterial communities in winter and summer in the chesapeake bay. | in the chesapeake bay, picocyanobacteria were usually 100-fold less abundant in winter than in summer. however, little is known about how picocyanobacterial populations shift between winter and summer in the bay. this is due mainly to undetectable winter picocyanobacterial populations in bacterial 16s rrna clone libraries. in this study, the winter and summer picocyanobacterial populations in the bay were detected using picocyanobacterium-specific primers and were compared based on the analysis ... | 2010 | 20228109 |
| primary screening of the bioactivity of brackishwater cyanobacteria: toxicity of crude extracts to artemia salina larvae and paracentrotus lividus embryos. | cyanobacteria are a diverse group of gram-negative bacteria that produce an array of secondary compounds with selective bioactivity against vertebrates, invertebrates, plants, microalgae, fungi, bacteria, viruses and cell lines. the aim of this study was to assess the toxic effects of aqueous, methanolic and hexane crude extracts of benthic and picoplanktonic cyanobacteria isolated from estuarine environments, towards the nauplii of the brine shrimp artemia salina and embryos of the sea urchin p ... | 2010 | 20411110 |
| [changes of bacterial community structure on reusing domestic sewage of daoxianghujing hotel to landscape water]. | a 16s rdna library was used to evaluate the bacterial diversity and identify dominant groups of bacteria in different treatment pools in the domestic sewage system of the beijing daoxianghujing hotel. the results revealed that there were many types of bacteria in the hotel domestic sewage, and the bacterial shannon-weaver diversity index was 3.12. in addition, epsilon proteobacteria was found to be the dominant group with the ratio of 32%. in addition, both the cfb phylum, fusobacteria, gamma pr ... | 2010 | 20623868 |
| are known cyanotoxins involved in the toxicity of picoplanktonic and filamentous north atlantic marine cyanobacteria? | eight marine cyanobacteria strains of the genera cyanobium, leptolyngbya, oscillatoria, phormidium, and synechococcus were isolated from rocky beaches along the atlantic portuguese central coast and tested for ecotoxicity. strains were identified by morphological characteristics and by the amplification and sequentiation of the 16s rdna. bioactivity of dichloromethane, methanol and aqueous extracts was assessed by the artemia salina bioassay. peptide toxin production was screened by matrix assis ... | 2010 | 20631874 |
| vertical tubular photobioreactor for semicontinuous culture of cyanobium sp. | we evaluated the kinetic culture characteristics of the microalgae cyanobium sp. grown in vertical tubular photobioreactor in semicontinuous mode. cultivation was carried out in vertical tubular photobioreactor for 2 l, in 57 d, at 30 °c, 3200 lux, and 12 h light/dark photoperiod. the maximum specific growth rate was found as 0.127 d(-1), when the culture had blend concentration of 1.0 g l(-1), renewal rate of 50%, and sodium bicarbonate concentration of 1.0 g l(-1). the maximum values of produc ... | 2010 | 21295968 |
| Phylogenetic, chemical and morphological diversity of cyanobacteria from Portuguese temperate estuaries. | Cyanobacteria from estuarine habitats have been poorly studied regarding diversity and potential bioactive compounds production compared with their fresh and marine waters' congeners. In this work, 44 cyanobacteria isolates characterised from three Portuguese estuarine environments. Identification was performed based on diacritical morphological features of the isolates (e.g. cell shape, cell size, presence/absence of sheaths) and on 16S rRNA gene sequences phylogenetic analysis. Diversity of pr ... | 2012 | 22093261 |
| morphological, phylogenetic and physiological studies of pico-cyanobacteria isolated from the halocline of a saline meromictic lake, lake suigetsu, japan. | small cyanobacteria (<2 µm, pico-cyanobacteria) are abundant in waters deeper than the oxic-anoxic zone in the halocline of a saline meromictic lake, lake suigetsu, fukui, japan. we have isolated 101 strains that were grouped into six groups by means of the phycobiliprotein composition and sequence homology of the intergenic spacer between the 16s and 23s rrna genes. significant growth was observed under weak green light (1.5 µmol m(-2) s(-1), approx. 460 to 600 nm), whereas the cells died under ... | 2011 | 22200643 |
| dispersal and phylogenetic diversity of nonmarine picocyanobacteria, inferred from 16s rrna gene and cpcba-intergenic spacer sequence analyses. | more than 20 synechococcus and cyanobium isolates were obtained from central european subalpine lakes and sequenced for their 16s rrna gene and part of the phycocyanin operon (cpc), specifically the intergenic spacer (igs) between cpcb and cpca, and corresponding flanking regions (cpcba-igs). maximum-likelihood analyses revealed the existence of at least six to seven clusters of nonmarine picocyanobacteria within the picophytoplankton clade and support the conjecture of global dispersal for some ... | 2003 | 12957969 |
| morphological transformation in a freshwater cyanobium sp. induced by grazers. | we document a remarkable morphological transformation, attributable to grazing by nanoflagellate ochromonas sp. ds, of a phycocyanin-rich freshwater cyanobium sp. (10-nr 98.2% similar 16s rrna gene sequence to the type species cyanobium gracile). the single cells aggregated into microcolonies (average size 40 microm) in the presence of the protist. colonies were characterized by hundreds of tubes (spinae), 100 nm to 1 microm long and 63 +/- 6 nm wide, on the surfaces of the cyanobium cells co-cu ... | 2007 | 17564619 |