RESUMO
The Bacteroides genus, the most prevalent anaerobic bacteria of the intestinal tract, carries a plethora of the mobile elements, such as plasmids and conjugative and mobilizable transposons, which are probably responsible for the spreading of resistance genes. Production of beta-lactamases is the most important resistance mechanism including cephalosporin resistance to beta-lactam agents in species of the Bacteroides fragilis group. In our previous study, the cfxA gene was detected in B. distasonis species, which encodes a clinically significant broad-spectrum beta-lactamase responsible for widespread resistance to cefoxitin and other beta-lactams. Such gene has been associated with the mobilizable transposon Tn4555. Therefore, the aim of this study was to detect the association between the cfxA gene and the presence of transposon Tn4555 in 53 Bacteroides strains isolated in Rio de Janeiro, Brazil, by PCR assay. The cfxA gene was detected in 11 strains and the Tn4555 in 15. The transposon sequence revealed similarities of approximately 96% with the B. vulgatus sequence which has been deposited in GenBank. Hybridization assay was performed in attempt to detect the cfxA gene in the transposon. It was possible to associate the cfxA gene in 11 of 15 strains that harbored Tn4555. Among such strains, 9 presented the cfxA gene as well as Tn4555, but in 2 strains the cfxA gene was not detected by PCR assay. Our results confirm the involvement of Tn4555 in spreading the cfxA gene in Bacteroides species.
Assuntos
Bacteroides/genética , Elementos de DNA Transponíveis/genética , beta-Lactamases/genética , Antibacterianos/farmacologia , Bacteroides/efeitos dos fármacos , Bacteroides/isolamento & purificação , Sequência de Bases , Southern Blotting , Brasil , Cefotaxima/farmacologia , Eletroforese em Gel de Ágar , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Resistência beta-Lactâmica/genéticaRESUMO
Foi desenvolvido um estudo comparativo para avaliar a eficácia do sistema de anaerobiose Anaerobac (Probac) no cultivo de bactérias anaeróbias estritas causadoras de infecções humanas. Como método de referência foi utilizado o sistema Gaspak (BBL), internacionalmente reconhecido pela eficácia. Os resultados revelaram que o sistema Anaerobac (Probac), além de ser prático e menos dispendioso, é eficaz no cultivo de diversas bactérias anaeróbias importantes no diagnóstico laboratorial de processos infecciosos