Search results for "16S"
showing 10 items of 464 documents
Characterisation of rpsL, rrs and embB mutations associated with streptomycin and ethambutol resistance in Mycobacterium tuberculosis.
2003
In order to characterise molecular mechanisms of first-line drug resistance in Mycobacterium tuberculosis and to evaluate the use of molecular markers of resistance (gene point mutations), we analysed 66 multi-drug-resistant (MDR) isolates from Latvian tuberculosis patients. They were all resistant to rifampin (RIF), isoniazid (INH) and streptomycin (SM), and 33 were resistant to ethambutol (EMB). Enzymatic digestion by MboII and nucleotide sequencing of the rpsL gene fragment detected a single nucleotide substitution K43R in 40 (61%) of the 66 SM-resistant M. tuberculosis isolates. Of the other 26 SM-resistant isolates, 16 (24%) had mutations at positions 513A--C and 516C--T of the rrs gen…
Use of nodulation pattern, stress tolerance, nodC gene amplification, RAPD-PCR and RFLP-16S rDNA analysis to discriminate genotypes of Rhizobium legu…
2005
Twenty-seven new Rhizobium isolates were obtained from root nodules of wild and crop legumes belonging to the genera Vicia, Lathyrus and Pisum from different agroecological areas in central and southern Italy. A polyphasic approach including phenotypic and genotypic techniques was used to study their diversity and their relationships with other biovars and species of rhizobia. Analysis of symbiotic properties and stress tolerance tests revealed that wild isolates, showed a wide spectrum of nodulation and a marked variation in stress tolerance compared with reference strains tested in this study. All rhizobial isolates (except for the isolate CG4 from Galega officinalis) were presumptively i…
Polyphasic taxonomic characterization of Lactobacillus rossiae isolates from Belgian and Italian sourdoughs reveals intraspecific heterogeneity.
2009
Abstract (GTG) 5 -PCR fingerprinting and pheS sequence analysis of 18 Lactobacillus rossiae isolates, mainly originating from Belgian and Italian artisan sourdoughs, revealed intraspecies grouping as evidenced by the delineation of three and two subgroups, respectively. On the other hand, 16S rRNA and rpoA gene sequence analysis and DNA–DNA hybridizations supported the accommodation of all isolates in a single species. No correlation between genetic and phenotypic heterogeneity was observed. Collectively, these data do not warrant taxonomic division of L. rossiae . On the other hand, the considerable differences in intraspecies sequence variation of L. rossiae isolates displayed by the pheS…
Vibrio renipiscarius sp. nov., isolated from cultured gilthead sea bream (Sparus aurata)
2015
Two strains of Gram-negative, facultatively anaerobic, slightly halophilic bacteria, isolated from healthy gilthead sea bream (Sparus aurata) cultured in Spanish Mediterranean fish farms, were different from their closest relatives,Vibrio scophthalmiandV. ichthyoenteri, by phenotypic, phylogenetic and genomic standards. The strains were negative for decarboxylase tests and lacked extracellular hydrolytic activities, but were able to fermentd-mannitol, sucrose, cellobiose andd-gluconate, among other carbohydrates. The major cellular fatty acids were C16:1and C16:0, in agreement with other species of the genusVibrio. Their 16S rRNA gene sequences were 98.4 and 97.2 % similar to those of the t…
Reinekea blandensis sp. nov., a marine, genome-sequenced gammaproteobacterium
2007
6 pages, 2 figures, 2 tables
Euzebyella saccharophila gen. nov., sp. nov., a marine bacterium of the family Flavobacteriaceae.
2010
Strain 7SM30T , an aerobic marine, Gram-negative, heterotrophic and yellow- to orange-pigmented bacterium isolated from seawater from Castellón, Spain, was characterized using a polyphasic approach. Analysis of the 16S rRNA gene sequence showed that the isolate represented a novel lineage within the family Flavobacteriaceae. The most closely related genera were Pseudozobellia, Zobellia and Kriegella. Cells of strain 7SM30T were non-motile rods that required sea salts for growth, used a wide variety of carbohydrates as sole carbon and energy sources and, unlike species of the genera Pseudozobellia and Zobellia, did not possess flexirubin-type pigment or hydrolyse agar. Strain 7SM30T containe…
Multilocus Sequence Analysis of the redefined clade Scophthalmi in the genus Vibrio.
2015
A Multilocus Sequence Analysis (MLSA) was performed on members of the Scophthalmi clade in the genus Vibrio, including type and reference strains of the species V. scophthalmi, V. ichthyoenteri, and 39 strains phenotypically identified as Vibrio ichthyoenteri-like, with the aim of better defining boundaries between these two closely related, fish-associated species. The type strain of V. ponticus, recently added to the clade Scophthalmi, was also included. The study was based on partial sequences of the protein-coding housekeeping genes rpoD, mreB, recA, ftsZ, and gyrB, and the 16S rRNA. While the 16S rRNA gene-based trees were unable to pull apart members of V. scophthalmi or V. ichthyoent…
Multilocus sequence analysis of the central clade of the genus Vibrio by using the 16S rRNA, recA, pyrH, rpoD, gyrB, rctB and toxR genes.
2009
The central clade of the genus Vibrio, also called the Vibrio core group, comprises six species that are tightly related (DNA–DNA reassociation values are very close to 70 % for most species pairs). Identification of novel strains to the species level within this group is troublesome and results are quite often dependent on the methodology employed. Therefore, this group represents an excellent framework to test the robustness of multilocus sequence analysis (MLSA) not only for inferring phylogeny but also as an identification tool without the need for DNA–DNA hybridization assays. The genes selected, 16S rRNA, recA, pyrH, rpoD, gyrB, rctB and toxR, were amplified by direct PCR from 44 Vibr…
Identification and typing of food-borne Staphylococcus aureus by PCR-based techniques.
2005
Abstract The possibility of using PCR for rapid identification of food-borne Staphylococcus aureus isolates was evaluated as an alternative to the API-Staph system. A total of 158 strains, 15 S. aureus , 12 other staphylococcal species, and 131 isolates recovered from 164 food samples were studied. They were phenotypically characterized by API-Staph profiles and tested for PCR amplification with specific primers directed to thermonuclease ( nuc ) and enterotoxin ( sea to see ) genes. Disagreement between the PCR results and API-Staph identification was further assessed by the analysis of randomly amplified polymorphic DNA (RAPD) profiles obtained with three universal primers (M13, T3, and T…
In vitro and in vivo sulfate reduction in the gut contents of the termite Mastotermes darwiniensis and the rose-chafer Pachnoda marginata.
2005
Sulfate-reducing bacteria (SRB) from termites have been assigned to the genus Desulfovibrio. Desulfovibrio intestinalis lives in the gut of the Australian termite Mastotermes darwiniensis. For the first time we were able to enrich and identify a sulfate-reducing bacterium from the gut of the rose-chafer Pachnoda marginata, which showed the highest 16S rDNA sequence identity (93%) to Desulfovibrio intestinalis and Desulfovibrio strain STL1. Compared to Mastotermes darwiniensis (1x10(7) cells of SRB per ml gut contents), sulfate-reducing bacteria occurred in higher numbers in the gut contents of Pachnoda marginata reaching cell titers of up to 2x10(8) cells per ml gut contents. In vitro sulfa…