Phospholipase production in morphological variants of Candida albicans

The yeast Candida albicans is considered a dangerous opportunist in a compromised host. Both phases of growth are thought to be pathogenic, however, evidence suggests that the hyphal phase is the more virulent. It has been proposed that the increased virulence lies in the ability of hyphae to digest and penetrate host tissue, thus enabling access of fungal cells to the deeper tissues. However, this one characteristic does not sufficiently explain the organism's success as a pathogen. Recently, high-frequency, colonial morphology switching systems were described in C. albicans. We obtained some of these variants and tested them for the ability to produce extracellular phospholipase(s), a generally accepted mechanism of pathogenesis in many microorganisms. Using egg yolk agar plates, we showed that all variants produced the enzyme. However, one produced significantly more than the others.