产淀粉酶和蛋白酶芽孢杆菌的筛选鉴定及其酶学性质分析

Screening and identification of amylase-and protease-producing Bacillus and their enzymatic property analysis

从分离自土壤的芽孢杆菌中筛选产淀粉酶和蛋白酶的菌株,对其进行形态学观察、生理生化试验及分子生物学鉴定,并对筛选菌株所产的淀粉酶和蛋白酶进行酶学性质分析。结果表明,筛选到产淀粉酶和蛋白酶菌株CX-47,菌株CX-47被鉴定为解淀粉芽孢杆菌(Bacillus amyloliquefaciens)。酶学性质分析结果表明,菌株CX-47所产淀粉酶和蛋白酶具有相同的最适反应温度(50℃)和最适反应p H(7.0);K^(+)和Ca^(2+)对菌株CX-47所产淀粉酶催化活性具有一定的促进作用,而Li^(+)和Mn^(2+)则有一定程度的抑制作用;K^(+)、Li^(+)、Ca^(2+)和Mn^(2+)均可显著提高菌株CX-47所产蛋白酶的活性(P<0.05)。

The amylase-and protease-producing strains were screened from Bacillus isolated from soil,and identified by morphological observation,physiological and biochemical tests,and molecular biological identification.The enzymatic properties of amylase and protease were analyzed.The results showed that the strain CX-47 producing amylase and protease was screened and identified as Bacillus amyloliquefaciens.The results of enzymatic properties analysis showed that the amylase and protease produced by the strain CX-47 had the same optimal reaction temperature (50℃) and optimal reaction p H (7.0).The catalytic activity of amylase produced by strain CX-47 could be promoted by K~+and Ca~(2+),but slightly inhibited by Li~+and Mn~(2+),while K~+,Li~+,Ca~(2+)and Mn~(2+)could significantly improve the activity of protease produced by strain CX-47 (P<0.05).