RESUMEN
The study describes a rapid approach for detection of common enteric bacterial pathogens, which involves partial amplification of the 16S rRNA gene by PCR using a colony from selective medium followed by restriction enzyme (RE) digestion using the EcoRI, HindIII and SalI enzymes. On the basis of RE digestion analysis different genera namely, Escherichia, Salmonella, Shigella, Vibrio, Campylobacter, Arcobacter, Yesinia and Listeria were differentiated.
Asunto(s)
Bacterias/aislamiento & purificación , Técnicas Bacteriológicas/métodos , Enfermedades Gastrointestinales/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo de Longitud del Fragmento de Restricción , Bacterias/clasificación , Bacterias/genética , Enzimas de Restricción del ADN/genética , Enzimas de Restricción del ADN/metabolismo , ADN Bacteriano/genética , ADN Bacteriano/metabolismo , Enfermedades Gastrointestinales/microbiología , Infecciones por Bacterias Gramnegativas/diagnóstico , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Grampositivas/diagnóstico , Infecciones por Bacterias Grampositivas/microbiología , ARN Ribosómico 16S/genéticaRESUMEN
Listeria monocytogenes is a foodborne pathogen associated with severe diseases in humans and animals. The genotypic analysis of 17 L. monocytogenes isolates recovered from humans in India during 2006-2009 using multiplex serotyping PCR allowing serovar predictions, conventional serology and by pulsed field gel electrophoresis (PFGE) is presented. The isolates were recovered from patients exhibiting various clinical conditions. A multiplex-PCR based serotyping assay revealed 88·24% (15/17) of the strains belonging to the serovar group 4b, 4d, 4e and 11·76% (2/17) to the serovar group 1/2b, 3b. Conventional serology indicated that 13 (76·47%) L. monocytogenes isolates to be of serotype 4b, 2 (11·76%) serotype 4d, and 2 (11·76%) serotype 1/2b. Ten ApaI and nine AscI pulsotypes were recognized among the 17 human isolates. PFGE analysis allowed discrimination among isolates of the same serotype and among isolates from the same sampling areas or those isolated from different areas. Thus, PFGE together with multiplex-PCR serotyping allows rapid discrimination of L. monocytogenes strains. In addition, the predominance of L. monocytogenes serotype 4b is of concern, as this serotype has been most frequently associated with human listeriosis outbreaks.