Survey for collagenase gene prtC in Porphyromonas gingivalis and Porphyromonas endodontalis isolated from endodontic infections

Collagenase is a potential virulence factor shown to be expressed by Porphy romonas gingivalis associated with periodontal disease. The purpose of this study was to use the polymerase chain reaction (PCR) to detect the presenc e of the collagenase gene (prtC) in 21 strains of Porphyromonas species iso lated from endodontic infections. Type strains for P. gingivalis (ATCC 3327 7), P. endodontalis (ATCC 35406), Prevotella intermedia (ATCC 25611), and P revotella nigrescens (ATCC 33563) were used as controls. When PCR primers s pecific for the 16S ribosomal RNA gene of P. gingivalis or P. endodontalis were used, 16 of the strains were identified as P. gingivalis, and five str ains were identified as P. endodontalis. The presence of the prtC gene for collagenase was detected using PCR. Amplicons were analyzed by agarose gel electrophoresis, with an 815 bp amplicon representing the presence of the c ollagenase gene. Type strain ATCC 33277 and all 16 clinical isolates of P. gingivalis produced the collagenase gene amplicon. Neither type strain ATCC 35406 nor the five strains from clinical isolates of P. endodontalis produ ced the collagenase gene amplicon. These results indicate that P. gingivali s from endodontic infections possesses the prtC gene. P. endodontalis does not seem to exhibit prtC. The virulence of P. gingivalis may be related to its production of collagenase.