Macromolecular syntheses during the cell cycles of yeast and hyphal phases of Candida albicans.

Abstract

Synchronous cultures of yeast and hyphal phases of Candida albicans showed exponential increases in RNA content and stepwise exponential increases in DNA content. The periods of DNA synthesis in the two phases coincided with one another and with the budding peaks of the yeast phase. Hyphae grown in synchronous cultures also showed an exponential increase in length. The hyphal phase was therefore normal. Hyphal nuclear division occurred after hyphal DNA synthesis. Germination was a unique event for a hypha and unlike yeast bud formation, preceded the first period of DNA synthesis. The exponential increase in RNA and DNA in asynchronous cultures of hyphae in serum paralleled the exponential increase in the numbers of cells in asynchronous cultures of yeasts in defined media. Thus there are no factors in serum which inhibit the normal exponential growth of C. albicans.