Gratuitous induction by N-acetylmannosamine of germ tube formation and enzymes for N-acetylglucosamine utilization in Candida albicans

Abstract

N-acetylmannosamine did not support the growth of C. albicans, and this sugar was not accumulated by cells. Incubation of starved yeast cells at 37°C with N-acetylmannosamine plus glucose resulted in germ tube formation. Furthermore, N-acetylmannosamine alone induced the uptake system for N-acetylglucosamine and the enzymes of the N-acetylglucosamine catabolic pathway to the same extent as the natural substrate. Induction of the uptake system and the enzymes was observed at 28°C without germ tube formation and at 37° C with germ tube formation. N-acetylmannosamine is thus a gratuitous inducer for enzymes of the N-acetylglucosamine pathway and germ tube formation in C. albicans.