黄海黄杆菌YS-9412-130低温碱性蛋白酶性质鉴定

Study on properties of low-temperature protease of Flavobacterium YS-9412-130

对黄海黄杆菌 YS- 94 12 - 130菌株产低温碱性蛋白酶的理化性质研究表明 ,该酶由 2 56个氨基酸组成 ,分子量为 330 0 0 Dar,等电点 p I为 9.4 5,米氏常数 Km为 5× 10 -3 m mol/ L;酶的最适作用p H范围为 9.5～ 10 .5,最适作用温度 30℃ ,具有一定的抗氧化稳定性。Ca2 +、Mn2 对酶有激活作用 ,而 Hg2 +、Ag+对酶有抑制作用。 DFP、NBS严重抑制酶的活性 ,而同时该酶也能被 EDTA抑制。结果表明该低温碱性蛋白酶为一新型的丝氨酸蛋白酶。

Physical and chemical properties of the low temperature protease from Flavobacterium YS 9412 130 are researched. It shows that the protease with certain stability of antioxidation consists of 256 amino acids, whose molecular weight is 33 kD, isoelectric point 9 45, K m value 5×10 -3 m mol/L, optimum pH ranging from 9 5 to 10 5, optimum temperature 30℃. Ions Ca 2+ and Mn 2+ activate the activity of the protease, while ions Hg 2+ and Ag + inhibit the enzyme activity, DFP and NBS can seriously inhibit the enzyme activity, the enzyme can also be inhibited by EDTA. Therefore, the low temperature alkaline protease is a new type of serine protease.