Purification and some properties of inducible N-acetylglucosamine kinase from Candida albicans.
N-Acetylglucosamine kinase (ATP:2-acetamido-2-deoxy-D-glucose 6-phosphotransferase, EC 2.7.1.59) catalyzes the first reaction in the inducible N-acetylglucosamine catabolic pathway of Candida albicans, an obligatory aerobic yeast. As a part of continuing biochemical studies concerning the regulation of gene expression in a simple eukaryote, N-acetylglucosamine kinase has been purified and characterized biochemically. The enzyme has been purified about 300-fold from the crude extract and its molecular weight of 75 000 has been determined by Sephadex G-100 gel filtration. Isolation and analysis procedures are described. The kinase reaction is optimal within a pH range of 7--8. The enzyme is strictly specific for GlcNAc as phosphate acceptor; ATP is the phosphoryl group donor for the kinase reaction and to a lesser extent dATP and CTP. Km values for GlcNAc and ATP are 1.33 mM and 1.82 mM, respectively. The enzyme required Mg2+, which may be replaced by other bivalent metal ions such as Mn2+, Ca2+, Ba2+ and Co2+ for a lesser degree of effectiveness. The purified enzyme is extremely sensitive to thermal denaturation and becomes completely inactive by heating at 65% C for 2 min. The enzyme is also inactivated by sulphydryl reagents such as p-chloromercuribenzene sulfonic acid and N-ethylmaleimide.
D002176:Candida albicans / Q000201:enzymology*; D002850:Chromatography, Gel; D004355:Drug Stability; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000494:pharmacology; D008970:Molecular Weight; D010770:Phosphotransferases / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism*; D017853:Phosphotransferases (Alcohol Group Acceptor); D013379:Substrate Specificity; D013439:Sulfhydryl Reagents / Q000494:pharmacology
D013439:Sulfhydryl Reagents; D010770:Phosphotransferases; D017853:Phosphotransferases (Alcohol Group Acceptor); C018716:N-acetylglucosamine kinase; D008274:Magnesium