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A hyaluronate lyase was obtained by cultivating Arthrobacter globiformis strain A152.The enzyme was purified to homogeneity from the supernatant by ammonium sulfate fracticnation,Q Sepharose Fast Flow,and Sephadex G-100 chromatography.The purification resulted in a 32.78-fold increase in hyaluronate lyase activity with specific activity of 297.2 U/mg.The molecular weight of the enzyme determined by SDS-PAGE was approximately 73.7 kDa.Using hyaluronic acid (HA) as a substrate,the maximal reaction rate (Vmax) and the Michaelis-Menten constant (Km) of hyaluronate lyase were found to be 4.76 μmol/min/ml and 0.11 mg/ml,respectively.The optimum pH and temperature values for hyaluronate lyase activity were pH 6.0 and 42 ℃,respectively.This enzyme was stable at pH 4-10,5-7,and 5-7 at 4,37,and 42 ℃,respectively.Investigation about temperature effects on hyaluronate lyase displayed that it was stable at 30-37 ℃ and also showed high activity at37 ℃.The enzymatic activity was enhanced by Ca2+ and was strongly inhibited by Cu2+ and SDS.These properties suggested that the hyaluronate lyase in this study could bring promising prospects in medical and industry applications.