产过氧化氢酶淀粉液化芽孢杆菌的筛选鉴定及酶学性质研究

Screening of Bacillus amyloliquefaciens producing hydrogen peroxidase and it’s enzymatic characterization

为了得到过氧化氢酶高产菌株,从江苏省土质属碱性地区的土壤中分离的102株菌株进行筛选,获得1株高过氧化氢酶活性的菌株,命名RU-22,酶活值达到189.2 U/mL。16S rDNA序列测定,为淀粉液化芽孢杆菌(Bacillus amyloliquefaciens)。通过对RU-22酶学性质的研究,确定该菌株的最适温度为40℃,热稳定性在40~50℃较好;最适pH为7,pH在6.0~8.0时酶的稳定性较好;Cu2+、Mg2+和Fe2+对酶活没有影响,Zn2+和Mn2+则对酶活有一定的抑制作用;经紫外照射2 h后酶活有明显的提高,为下一步淀粉液化芽孢杆菌、过氧化氢酶的实际应用奠定了一定的基础。

In order to obtain the strain yielding high hydrogen peroxidase activity,the 102 strains isolated from alkaline soil in Jiangsu province were screened,obtained one strain of high catalase activity,named RU-22,and the enzyme activity reached 189.2 U/mL.The strain RU-22 was identified as Bacillus amyloliquefaciens through physiological biochemistry and 16 S rDNA sequence.The enzymatic properties of the catalase produced by RG-22 were optimized.The optimal temperature was 40℃,and the enzymatic properties was stable in temperature 40~50℃.The optimal pH was 7,and the stability was in pH 6~8.Cu2+,Mg2+and Fe2+had no effect on enzyme activity,Zn2+and Mn2+had a certain inhibition.After 2 hours UV irradiation,the enzyme activity was obviously increased.The success of the catalase high-yield strains screening and optimizing laid a certain foundation for the further practical application of Bacillus amyloliquefaciens and the catalase.