Glucose Promotes Stress Resistance in the Fungal Pathogen Candida albicans

Authors

Alexandra Rodaki, University of Aberdeen
Iryna M. Bohovych, University of AberdeenFollow
Brice Enjalbert, University of Aberdeen
Tim Young, Discovery Biology, Pfizer Ltd
Frank C. Odds, University of Aberdeen
Neil A.R. Gow, University of Aberdeen
Alistair J.P. Brown, University of AberdeenFollow

Document Type

Article

Date of this Version

2009

Citation

Molecular Biology of the Cell Vol. 20, 4845–4855, November 15, 2009

Comments

© 2009 by The American Society for Cell Biology

Abstract

Metabolic adaptation, and in particular the modulation of carbon assimilatory pathways during disease progression, is thought to contribute to the pathogenicity of Candida albicans. Therefore, we have examined the global impact of glucose upon the C. albicans transcriptome, testing the sensitivity of this pathogen to wide-ranging glucose levels (0.01, 0.1, and 1.0%). We show that, like Saccharomyces cerevisiae, C. albicans is exquisitely sensitive to glucose, regulating central metabolic genes even in response to 0.01% glucose. This indicates that glucose concentrations in the bloodstream (approximate range 0.05–0.1%) have a significant impact upon C. albicans gene regulation. However, in contrast to S. cerevisiae where glucose down-regulates stress responses, some stress genes were induced by glucose in C. albicans. This was reflected in elevated resistance to oxidative and cationic stresses and resistance to an azole antifungal agent. Cap1 and Hog1 probably mediate glucose-enhanced resistance to oxidative stress, but neither is essential for this effect. However, Hog1 is phosphorylated in response to glucose and is essential for glucose-enhanced resistance to cationic stress. The data suggest that, upon entering the bloodstream, C. albicans cells respond to glucose increasing their resistance to the oxidative and cationic stresses central to the armory of immunoprotective phagocytic cells.