Demonstration of virulent genes within Listeria and Klebsiella isolates contaminating the export quality frozen shrimps

Abstract

In the previously studied export quality shrimp samples, presence of a range of pathogenic bacteria including <em>Listeria</em> spp. and <em>Klebsiella</em> spp. were detected. The presence of <em>eae</em> gene in <em>Escherichia</em> <em>coli</em>, <em>aero</em> specific gene in <em>Aeromonas</em> spp., and <em>sodB</em> gene in <em>Vibrio</em> spp. were observed which might confer the associated virulence. Present study further attempted to detect the existence of virulent genes in <em>Listeria</em> spp. and <em>Klebsiella</em> isolates from the same shrimp samples through the gene specific polymerase chain reaction (PCR). Visualization of bands of <em>iap</em> (457 bp) and <em>gyr</em>B2 (711 bp) genes after PCR amplification referred the presence of virulence strains of <em>Listeria</em> spp. and <em>Klebsiella</em> spp., respectively in the export quality shrimp samples. Together with the previous findings of virulence genes of several pathogenic bacteria, the outcomes of current study further conferred the possible detrimental impact of the export quality frozen shrimps as and when consumed.