青藏高原土壤低温产蛋白酶菌株的筛选及酶学性质研究

Screening and enzymatic characterizations of a low temperature protease-producing strain from Qinghai-Tibet Plateau soil

从青藏高原土壤样品分离保藏的菌种中筛选到低温条件下产蛋白酶菌株LS20-2,对其进行生理生化试验以及分子生物学鉴定,并对其发酵液进行酶学性质初步研究。结果表明,该菌被鉴定为皮氏类芽孢杆菌(Paenibacillus peoriae),产蛋白酶的最适反应p H值为7.0,最适温度为40℃。在p H5.0~7.0之间、温度0~40℃时酶活稳定,金属离子Fe^(2+)、Zn^(2+)及Triten X-100能抑制蛋白酶活性,金属离子Mn^(2+)及表面活性剂Tween-20、Tween-80能提高蛋白酶活性。

A low temperature protease-producing strain,named as LS20-2, was screened from the Qinghai-Tibet Plateau soil samples. After physiolog-ical and biochemical identification and molecular biology, and the enzymatic properties of the fermentation broth was preliminarily studied. Results showed that the strain was identified as Paenibacillus peoriae, the optimal pH and temperature for the protease were 7.0 and 40 ℃,respectively. The protease activity was stable at pH 5.0-7.0 and temperature 0-40 ℃ . Metal ions Fe2＋, Zn2＋ and Triten X-100 could inhibit protease activity, Mn2＋ and surfactant Tween-20, Tween-80 could improve the activity of protease.