Characterization of a Porphyromonas gingivalis gene prtK that encodes a lysine-specific cysteine proteinase and three sequence-related adhesins

Porphyromonas gingivalis extracellular arginine- and lysine-specific protei nases have been implicated as major virulence factors in the development of adult periodontitis. We have previously purified a 48-kDa lysine-specific cysteine proteinase, designated PrtK48, from a P. gingivalis W50 cell-assoc iated multiprotein complex. PrtK48 was non-covalently associated with three sequence-related adhesins designated PrtK39, PrtK15 and PrtK44 in the mult iprotein complex. In this study we cloned and characterized the gene, desig nated prtK, that encodes a polyprotein that is post-translationally process ed to yield the Lys-specific proteinase PrtK38 and the three sequence-relat ed adhesins PrtK39, PrtK15 and PrtK44.