Objective: To investigate the genotypic characterization of Porphyromonas gingivalis (Pg) and the heterogeneity of a potential virulence factor-PrtC.
Methods: Arbitrarily primed polymerase chain reaction (AP-PCR) was applied to 80 Pg strains isolated from 24 unrelated Chinese periodontitis patients. PCR reaction was used to detect a fragment of the collagenase gene (PrtC gene). To evaluate the sequence heterogeneity of the Pg PrtC genes, sequence analysis of four PrtC gene of clinical isolates was performed.
Results: Random primer OPA-05 and OPA-17 distinguished 7 AP-PCR profiles (I through VII). The majority of the strains belonged to type VII which accounted for 25.8%. A 548bp fragment of PrtC gene was detected from 24 clinical strains. The PCR products were verified by the restriction endonucleases PstI and PvuI. Sequence analysis showed 4 PrtC genes were heterogeneous in their nucleotide composition and differed from reference strain Pg 53977.
Conclusions: The results demonstrated genetic diversity existed among these clinical strains isolated from Chinese periodontitis patients and the PrtC genes are heterogeneous in their nucleotide sequence.