Differential effects of growth temperatures on inactivation and mutation of Candida albicans by ultraviolet radiation.

Abstract

Candida albicans exhibits greater susceptibility to inactivation by ultraviolet (uv) radiation if grown before or after irradiation at 37° C rather than 25° C. Caffeine, acriflavin or amino acid analogues potentiate inactivation during postirradiation growth at 37° C but have little effect at 25° C. In contrast to inactivation, mutation induction by uv is unaffected by pre- or postirradiation growth temperatures or by metabolic antagonists. These findings are not explicable in terms of possible effects of growth temperatures on known mechanisms for repair of uv damaged DNA. They are consistent, however, with a previous proposal that a temperature dependent mechanism for dark recovery exists in C. albicans which involves synthesis of protein essential for repair of lethal, non-genetic uv damage.