title: Virulence of a polymicrobic complex, Treponema denticola and Porphyromonas gingivalis, in a murine model.
abstract: The effect of a polymicrobic infection employing Treponema denticola and Porphyromonas gingivalis in the murine lesion model was used to determine the synergistic virulence of these two periodontopathic bacteria. At high doses of P. gingivalis W50, addition of T. denticola in the infection mixture had no effect on the formation and size of the spreading lesion caused by this microorganism. However, at low P. gingivalis challenge doses, T. denticola significantly enhanced the virulence of P. gingivalis compared with monoinfection of this microorganism. A potential role of the trypsin-like protease enzyme activity of P. gingivalis in this synergistic virulence was tested using P. gingivalis mutants deficient (i.e., BEI) or devoid (i.e., NG4B19) of this protease activity. These findings demonstrated that T. denticola-P. gingivalis complexes exhibit enhanced virulence in this model and that even using a polymicrobic challenge infection, the trypsin-like protease activity was important to P. gingivalis virulence expression.
authors.affiliation: Department of Periodontics, University of Texas Health Science Center at San Antonio 78284, USA.
authors.forename: L
authors.initials: L
authors.lastname: Kesavalu
authors.forename: S C
authors.initials: SC
authors.lastname: Holt
authors.forename: J L
authors.initials: JL
authors.lastname: Ebersole
mesh_terms: D000038:Abscess / Q000382:microbiology; D000818:Animals; D001426:Bacterial Proteins / Q000378:metabolism; D004195:Disease Models, Animal; D017753:Ecosystem; D005260:Female; D051379:Mice; D008813:Mice, Inbred ICR; D016966:Porphyromonas gingivalis / Q000201:enzymology / Q000472:pathogenicity*; D051381:Rats; D012697:Serine Endopeptidases / Q000378:metabolism; D018709:Statistics, Nonparametric; D014208:Treponema / Q000472:pathogenicity*; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D012697:Serine Endopeptidases