对从海水中分离得到的嗜水气单胞菌所产的几丁质酶的酶学性质进行研究。其最适pH为7.0左右，最适反应温度为45 ℃左右。在40 ℃以下有良好的热稳定性，12 h仍有50%残余酶活。Mg2+对酶有激活作用，Cu2+和Al3+对酶有明显的抑制作用。该酶对底物的亲和力很大，水解几丁质的Km值为29.15 g/L。

A chitinase-producing bacteria, isolated from sea water, was identified as Aeromonas hydrophila. The characteristics of purified chitinase from fermented broth by ammonium sulfate fractionation and dialysis were studied. Its optimal pH value and temperature were 7.0 and 45 ℃, respectively, using colloid chitin as substrate. The chitinase showed high thermal stability, with a residue activity of 50% remained after incubation of the enzyme in water for 12 h at 40 ℃. Metal ions had different effects on the chitinase activity which could be improved by Mg2+, but obviously inhibited by Cu2+ and Al3+. Its Michaelis constant Km in the hydrolysis of chitin was 29.15 g/L, indicating that the chitinase possessed high substrate affinity.