Biol. Pharm. Bull. 28(7) 1281—1285 (2005)

in a compromised host. Among the various Candida species, C. albicans is the most medically important. In 1961, Hasenclever and Mitchell identified two serotypes in C. albicans species, A and B, demonstrating that the pathogenicity of both types was identical in mice when the inoculation of the cells was conducted via the intravenous route. The acid proteinase (AP) produced by the C. albicans species has attracted a great deal of attention as a virulence factor in the pathogenesis of human and animal infections, though the existence of contradictory findings has been pointed out. It has been shown that the recovery of the serotype A strains was more pronounced than that of serotype B in mice when both strains were orally inoculated with mixtures of the two strains. Borg and Rüchel reported that different strains of serotype B, during infection into phagocytes, expressed an AP antigen only on blastoconidia, while filamentous cells of these strains appeared to be nonproteolytic, and that the serotype A strains expressed the antigen on the cells of both types. During the course of screening the proteinase-producing Candida strains, we found that the C. albicans NIH B-792 (serotype B) strain produced a large amount of AP in the culture broth compared to the C. albicans NIH A-207 (serotype A) strain when cultured in a yeast carbon-based medium supplemented with bovine serum albumin (BSA) as the sole nitrogen source. In this paper, we have compared the properties of the APs produced by the C. albicans NIH A-207 and NIH B-792 strains in order to determine the relevance of these enzymes in Candidosis.