Secretion of acid proteinases by different species of the genus Candida.

Strains of several Candida species that are isolated from humans aside of C. albicans have been screened for secretion of acid proteinases. A third of the strains of C. tropicalis was strongly proteolytic, other strains of this species were moderately or virtually nonproteolytic; the variety of activities resembled pattern found among strains of C. albicans (32). Strains of C. parapsilosis produced 24% of the proteolytic activity of strongly proteolytic strains of C. tropicalis. The proteolytic activity of C. pseudotropicalis, C. krusei, and C. glabrata accounted for 7.5, 2.0, and 0.8% respectively. Four strains of C. guilliermondii developed strain-specific proteolysis after prolonged cultivation only. Five proteinases from strains of C. tropicalis cross reacted immunologically as did five proteinases from C. albicans. Interspecific cross reaction, though, was not observed when certain sera from rabbits were employed.