A PCR protocol using inl gene as a target for specific detection of Listeria monocytogenes

Abstract

Polymerase chain reaction is a powerful technique for detection of pathogens in foods. It is a rapid procedure with both sensitivity and specificity for quick detection and identification of specific pathogenic bacteria from different sources. Listeria monocytogenes detection methods based on PCR amplification of the iap, prfA and hly gene sequences have been reported. The present study undertakes the development of an alternative PCR method using the inl gene sequences as a target to detect pathogenic L. monocytogenes. The presence of a unique and specific DNA amplification fragment of 760 bp for the intragenic repeats B of the inlA gene in all strains of L. monocytogenes as compared to none in other Listeria and unrelated Gram positive and Gram negative species confirms that this procedure is an alternative PCR protocol for detection of L. monocytogenes.