RESUMO
Abstract. Ribosomal DNA (rDNA) sequences are widely used for phylogenetic and bacterial identification. However, rDNA of different species often reveals similar or identical same sequences. This study employed the bacterial stable small RNA (ssrA) gene encoding transfer-messenger RNA (tmRNA) as a tool for identification of Staphylococcus aureus, Enterococcus spp, Pseudomonas spp and Enterobacteriaceae from clinical isolates as representative groups using PCR and species specific primers. The method correctly identified 11 standard strains and 99 clinical isolates. Quantitative PCR revealed a limit of detection of 10(-5) µg of DNA for S. aureus and Enterococcus spp, and 10(-6) µg for Pseudomonas spp and Enterobacteriaceae. Further studies with a greater number of bacteria especially from clinical samples will need to be undertaken before this bacterial molecular marker can be applied in a clinical setting.
Assuntos
Enterobacteriaceae/genética , Enterococcus/genética , Pseudomonas/genética , RNA Bacteriano/genética , Proteínas de Ligação a RNA/genética , Staphylococcus aureus/genética , Técnicas de Tipagem Bacteriana , Humanos , Tipagem Molecular , Filogenia , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , RNA de Transferência/genéticaRESUMO
The purpose of this study was to examine the in vitro susceptibilities to antimicrobial agents and genetic diversity of 195 clinical strains of Salmonella spp., which were isolated and examined for the extended-spectrum ß-lactamase (ESBL) blaCTX-M gene and the presence of gyrA, gyrB, parC, and parE genes mutations in Hyogo, Japan, from 2009 to 2012. Forty-three of the 195 strains were antimicrobial resistant. Two Salmonella enterica subsp. enterica strains, 1 serovar Schwarzengrund, and 1 serovar Enteritidis were identified as ESBL-producing strains possessing blaCTX-M-15 and blaCTX-M-2, respectively. Among 8 nalidixic acid-resistant strains, 7 had mutations in gyrA alone or in gyrA and parC. In conclusion, we identified CTX-M ESBL-producing Salmonella clinical strains with multidrug resistance. Further studies are needed to monitor these serious drug-resistant Salmonella strains in Japan.
