Search results for "Sequence analysis"
showing 10 items of 1349 documents
The Evolutionary Fate of Nonfunctional DNA in the Bacterial Endosymbiont Buchnera aphidicola
2004
Reduction of the genome size in endosymbiotic bacteria is the main feature linked to the adaptation to a host-associated lifestyle. We have analyzed the fate of the nonfunctional DNA in Buchnera aphidicola, the primary endosymbiont of aphids. At least 164 gene losses took place during the recent evolution of three B. aphidicola strains, symbionts of the aphids Acyrthosiphon pisum (BAp), Schizaphis graminum (BSg), and Baizongia pistacia (BBp). A typical pattern starts with the inactivation of a gene, which produces a pseudogene, and is followed by the progressive loss of its DNA. Our results show that during the period from the separation of the Aphidinae and Pemphiginae lineages (86-164 MYA…
Pseudomonas litolaris sp. nov., isolated from mediterranean seawater
2012
Strains 2SM5T and 2SM6, two strictly aerobic chemo-organotrophic gammaproteobacteria, were isolated from Mediterranean seawater off the coast of Vinaroz, Castellón, Spain, in February, 1990. They were extensively characterized by a polyphasic study that placed them in the genus Pseudomonas. Phylogenetic analysis of 16S rRNA gene sequences showed that both strains shared 100 % sequence similarity and were closely related to members of the Pseudomonas pertucinogena clade, with less than 97.3 % similarity to strains of established species; Pseudomonas xiamenensis was the closest relative. Analysis of sequences of three housekeeping genes, rpoB, rpoD and gyrB, further confirmed the phylogenetic…
Treponema isoptericolens sp. nov., a novel spirochaete from the hindgut of the termite Incisitermes tabogae.
2008
A novel spirochaete, Treponema sp. strain SPIT5T, was isolated from hindgut contents of the drywood termite Incisitermes tabogae (Snyder). The cells of strain SPIT5T were motile, helical in shape, 0.4-0.5 microm in diameter and generally 12-20 microm long. The strain is obligately anaerobic and ferments different mono-, di- and oligosaccharides by forming ethanol as the main liquid fermentation end product. Furthermore, strain SPIT5T was able to grow anaerobically with yeast extract as sole carbon and energy source. Fastest growth was obtained at 30 degrees C, the temperature at which the termites were also grown. The optimum pH for growth was 7.2, with a range of pH 6.5-8.0. The cells poss…
Jannaschia rubra sp. nov., a red-pigmented bacterium isolated from sea water.
2005
A Gram-negative, slightly halophilic, strictly aerobic, chemo-organotrophic bacterium was isolated from Mediterranean sea water near Valencia (Spain). Comparison of the almost complete 16S rRNA gene sequence showed that strain 4SM3T belonged to the Roseobacter group, with Jannaschia helgolandensis as its closest relative, with a similarity of 98·7 %. DNA–DNA hybridization analysis showed that the Mediterranean isolate had a level of relatedness of less than 42 % with J. helgolandensis and therefore that it represented a novel species of the genus Jannaschia. Phenotypic characteristics gave further evidence that the two organisms are not related at the species level. Isolate 4SM3T grows on s…
Identification of Carnobacterium, Lactobacillus, Leuconostoc and Pediococcus by rDNA-based techniques
2003
Summary Ribosomal DNA-based techniques including the analysis of profiles generated by ISR amplification, ISR restriction and ARDRA have been evaluated as molecular tools for identifying Carnobacterium, Lactobacillus, Leuconostoc and Pediococcus. They have been applied for the molecular characterization of 91 strains with the following identities: eight Carnobacterium including the eight type species of the genus; 61 Lactobacillus including 40 type strains out of 45 species, 13 Leuconostoc, out of them 11 are type strains and three are subspecies of Lc. mesenteroides; and nine strains representing the six species of genus Pediococcus. The genetic relationship displayed between these species…
Diversity of rhizobia nodulating wild shrubs of Sicily and some neighbouring islands
2008
Abstract Legume shrubs have great potential for rehabilitation of semi-arid degraded soils in Mediterranean ecosystems as they establish mutualistic symbiosis with Nfxing rhizobia. Eighty-eight symbiotic rhizobia were isolated from seven wild legume shrubs native of Sicily (Southern Italy) and grouped in operational taxonomic units (OTU) by analysis of the ribosomal internal transcribed spacer (ITS) polymorphism. Partial sequencing of 16S rRNA gene of representative isolates of each OTU revealed that most Genisteae symbionts are related to Bradyrhizobium canariense, B. japonicum and B. elkanii. Teline monspessulana was the only Genistea nodulated by Mesorhizobium strains, and Anagyris foeti…
Lactobacillus aquaticus sp. nov., isolated from a Korean freshwater pond.
2009
A Lactobacillus strain, IMCC1736T, was isolated recently from a Korean freshwater pond following an extensive study of the microbial community in this ecosystem. Its 16S rRNA gene was sequenced and phylogenetic analysis placed this strain within the Lactobacillus salivarius group, closely related to Lactobacillus satsumensis NRIC 0604T, with 97.9% sequence similarity. In the present work, the taxonomic status of strain IMCC1736T has been re-evaluated. It was characterized phylogenetically, genotypically and phenotypically and, based on DNA-DNA hybridization values, this strain represents a novel Lactobacillus species. Strain IMCC1736T can be differentiated genotypically from its closest rel…
Psychrotolerant Sulfate-reducing Bacteria from an Oxic Freshwater Sediment Description of Desulfovibrio cuneatus sp. nov. and Desulfovibrio litoralis…
1998
The most abundant culturable sulfate-reducing bacteria were isolated from the littoral sediment of the oligotrophic Lake Stechlin. The strains STL1 and STL4 were obtained from the oxic uppermost layer, while strain STL6 was isolated from the anoxic zone in 20 to 30 mm depth. The isolates showed a striking morphological feature in tapering off at one end of the cell. Physiological characteristics related them to the genus Desulfovibrio. They contained desulfoviridin. H2, formate, pyruvate, lactate, and fumarate were utilized with sulfate, sulfite, thiosulfate, or elemental sulfur as electron acceptors. All isolates were able to reduce oxygen and survived 120 h of aeration. However, aerobic g…
Sphingobium aromaticiconvertens sp. nov., a xenobiotic-compound-degrading bacterium from polluted river sediment.
2007
A bacterial strain capable of degrading some monochlorinated dibenzofurans, designated RW16T, was isolated from aerobic River Elbe sediments. The strain was characterized based on 16S rRNA gene sequence analysis, DNA G+C content, physiological characteristics, polyamines, ubiquinone and polar lipid pattern and fatty acid composition. This analysis revealed that strain RW16T represents a novel species of the genus Sphingobium. The DNA G+C content of strain RW16T, 60.7 mol%, is the lowest yet reported for the genus. 16S rRNA gene sequence analysis placed strain RW16T as an outlier in the genus Sphingobium. The name Sphingobium aromaticiconvertens sp. nov. is proposed for this dibenzofuran-min…
Vibrio ponticus sp. nov., a neighbour of V fluvialis-V. furnissii clade, isolated from gilthead sea bream, mussels and seawater.
2004
A new Vibrio species, Vibrio ponticus, is proposed to accommodate four marine bacteria isolated from sea water, mussels and diseased sea bream (Sparus aurata), at the Mediterranean coast of Spain. Strains are Gram negative, slightly halophilic bacteria that require Na+ ion for growth, oxidase and catalase positive, negative for arginine dihydrolase and ornithine decarboxylase but positive for lysine decarboxylase and indole, and utilize beta-hydroxybutyrate as a sole carbon source. Phylogenetic analysis locate these marine bacteria in the vicinity of the V. fluvialis-V. furnissii clade, sharing with these two species 16S rDNA sequence similarities slightly above 97% (97.1 and 97.3%, respect…