The interaction of [3H]miconazole with Candida albicans.

During the stationary phase of a batch culture, Candida albicans develops the ability to take up large amounts of [3H]miconazole, and this occurs over the same period of time as the cells become resistant to miconazole-induced K+ release. Cell walls isolated from C. albicans also take up [3H]miconazole, and it is likely that the cell wall is the site of the association of [3H]miconazole with intact cells. Miconazole interaction with C. albicans is freely reversible and relatively nonspecific, and evidence suggests the involvement of hydrophobic bonding. Although fractionation studies were not exhaustive, results suggest that [3H]miconazole associates with glycoprotein and lipid in the matrix of the cell wall. Development of the ability to take up [3H]miconazole requires a low pH in the culture medium at the end of the growth phase, and efficient aeration, and was found to occur most rapidly in the presence of 0.3 mM sodium azide. The nature of the changes that occur during incubation through the stationary phase, and also similar changes that take place during cell wall preparation, and their relationship to phenotypic miconazole resistance are discussed.