Characterization of the gene encoding 200-kDa Porphyromonas gingivalis protein that reacts to sera from periodontitis patients.

Porphyromonas gingivalis, a Gram-negative anaerobic bacterium, is considered to be one of the major etiologic agents of adult periodontitis. We previously succeeded in molecular cloning of a 200-kDa antigenic protein (200-k AP) from P. gingivalis 381 by immunoscreening using sera from severe periodontitis patients and designated it as pMD101.