A POLYMERASE-CHAIN-REACTION (PCR) METHOD FOR THE IDENTIFICATION OF COLLAGEN ADHESIN GENE (CNA) IN STAPHYLO COCCUS-INDUCED PROSTHESIS INFECTIONS

Staphylococci are well-recognized pathogens of foreign body-associated infections. The pathogenesis of such infections involves an initial s tep of contact between the colonizing bacterium and the biomaterial, w ith subsequent colony formation. Several studies have been devoted to identify adhesion mechanisms for these bacteria. Slime in particular h as been extensively investigated. Recently,considerable attention has been given to the host protein receptors that have been shown in in vi tro assays to serve as substrates for bacterial adherence. To determin e the importance of the collagen adhesin as virulence factor in Staphy lococcus-induced prosthesis infection, a simple and reliable method us ing a polymerase chain reaction (PCR) was devised to identify collagen adhesin gene (cna). By using lysates of ten strains from orthopedic p rostheses (5 Staphylococcus aureus and 5 Staphylococcus epidermidis) a nd two 20-oligonucleotides as primers, a 192-bp region of the cna gene was amplified by PCR and detected by agarose gel electrophoresis. Res ults obtained by this method were in accordance with those obtained by the in vitro phenotypic characterization of binding ability to collag en of Staphylococcus strains.