Purification and Properties of N‐Acetylglucosamine Kinase from Human Gastric Mucosa

N ‐Acetylglucosamine kinase from the human gastric mucous membrane was purified about 170‐fold. The purified enzyme is specific for N ‐acetylglucosamine with slight phosphorylation of N ‐acetylmannosamine. The aminosugar product of the enzymatic reaction was identified as N ‐acetylglucosamine 6‐phosphate. The Km for N ‐acetylglucosamine is 0.11 K m and for ATP 3.03 mM. The pded enzyme is stable at +4 °C for three days, labile to dialysis and irreversibly inhibited by p ‐chloromercuribenzoate. The molecular weight of the enzyme was 77000.