Characterization of the CaNAG3, CaNAG4, and CaNAG6 genes of the pathogenic fungus Candida albicans: possible involvement of these genes in the susceptibilities of cytotoxic agents.

CaNAG3, CaNAG4, and CaNAG6 form a gene cluster with CaNAG1 CaNAG2 and CaNAG5 that are responsible for glucosamine-6-phosphate deaminase, N-acetylglucosamine-phosphate deacetylase and N-acetylglucosamine kinase, but their functions largely remain unclear. In this study, Candida albicans cells carrying null mutations in either CaNAG3, CaNAG4, or CaNAG6 were generated and characterized. They showed increased susceptibility to cycloheximide and attenuated virulence in mice. More profound effects were observed when both CaNAG3 and CaNAG4, which are highly related to each other, were disrupted. Thus, it seems that CaNAG3, CaNAG4, and CaNAG6 are involved in drug sensitivity and virulence in C. albicans.