HK1 and candidiasis: Singh et al. (2001) observed that C. albicans mutant with disruption in the N-acetylglucosamine (GlcNAc) catabolic pathway gene cluster (nag cluster mutant), including the GlcNAc-6-phosphate deacetylase (dac1), glucosamine-6-phosphate deaminase (nag1), and GlcNAc kinase (hxk1) genes, was not able to grow on amino sugars, exhibited highly attenuated virulence in a murine systemic candidiasis model but showed hyperfilamentation under stress-induced filamentation conditions.