title: A member of the peptidase M48 superfamily of Porphyromonas gingivalis is associated with virulence in vitro and in vivo.
abstract: BACKGROUND
  In vivo-induced antigen technology was previously used to identify 115 genes induced in Porphyromonas gingivalis W83 during human infection. One of these, PG2197, a conserved hypothetical protein which has homology to a Zn-dependent protease, was examined with respect to a role in disease.
  
  
  METHODS
  The expression of PG2197 in human periodontitis patients was investigated, but as there is increasing evidence of a direct relationship between P. gingivalis and cardiovascular disease, a mutation was constructed in this gene to also determine its role in adherence, invasion, and persistence within human coronary artery endothelial cells (HCAEC) and neutrophil killing susceptibility.
  
  
  RESULTS
  Plaque samples from 20 periodontitis patients were analyzed by real-time PCR, revealing that PG2197 was expressed in 60.0% of diseased sites compared to 15.8% of healthy sites, even though P. gingivalis was detected in equal numbers from both sites. The expression of this gene was also found to be up-regulated in microarrays at 5 and 30 min of invasion of HCAEC. Interestingly, a PG2197 mutant displayed increased adherence, invasion, and persistence within HCAEC when compared to the wild-type strain.
  
  
  CONCLUSIONS
  This gene appears to be important for the virulence of P. gingivalis, both in vivo and in vitro.
authors.affiliation: Department of Oral Biology, Center for Molecular Microbiology, College of Dentistry, University of Florida, Gainesville, FL, USA.
authors.forename: Sheila
authors.initials: S
authors.lastname: Walters
authors.forename: Myriam
authors.initials: M
authors.lastname: Bélanger
authors.forename: Paulo H
authors.initials: PH
authors.lastname: Rodrigues
authors.forename: Joan
authors.initials: J
authors.lastname: Whitlock
authors.forename: Ann
authors.initials: A
authors.lastname: Progulske-Fox