IDENTIFICATION OF A GENE ENCODING A METHYL-ACCEPTING CHEMOTAXIS-LIKE PROTEIN FROM CAMPYLOBACTER-COLI AND ITS USE IN A MOLECULAR TYPING SCHEME FOR CAMPYLOBACTERS

Using PCR amplification with degenerate primers, a gene (tlpA) from Ca mpylobacter coli encoding a putative 63.0 kDa polypeptide which exhibi ted significant identity with bacterial methyl-accepting chemotaxis pr oteins (MCPs) was identified. A mutant containing an inactivated copy of the tlpA gene showed a wild-type chemotactic response to all of the chemo-attractants tested. A DNA probe based on the Highly Conserved D omain (HCD) of TlpA revealed the presence of multiple copies of genes encoding MCP-Iike proteins in both Camp. coli and Camp. jejuni. The ar rangement of restriction sites within, and proximal to, genes with hom ology to the HCD probe varied among strains, resulting in a high degre e of polymorphism. It is demonstrated here that a DNA probe comprising the HCD region of;MCP-like proteins can be used, in Southern hybridiz ation-based assays, to provide novel information which allows the disc rimination of individual strains of Camp. coli and Camp. jejuni.