华中农业大学学报2025，Vol.44Issue(4)：143-149,7.DOI:10.13300/j.cnki.hnlkxb.2025.04.014
α-淀粉酶产生菌的筛选鉴定及Ba8a蛋白的酶学特性
Isolation and identification of α-amylase producing bacteria and enzymatic characteristics of Ba8a protein
摘要
Abstract
A high-yield strain of α-amylase,named as SCUEC8 strain,was isolated from fermented straw in bovine stomach with selective culture medium to solve the problem of decomposing crop straw.The strain isolated was identified as Bacillus subtilis based on the morphological observation and physiologi-cal and biochemical characteristics combined with comparative analysis of 16S rDNA sequence.The genom-ic DNA of SCUEC8 strain was used as template to amplify the ba8a gene of α-amylase by PCR.The re-combinant plasmid pET28a(+)-ba8a was constructed and transformed into the E.coli BL21 strain for heterologous expression to further analyze the enzymatic characteristics of Ba8a protein expressed.The re-sults showed that the length of ba8a gene was 1 434 bp,and the molecular weight of the Ba8a protein was 52.9 ku.The relative enzyme activity of Ba8a protein was relatively high with pH 5.0 and a reaction temper-ature of 45℃.Mn2+had a higher effect on promoting the enzyme activity of Ba8a protein,while Cu2+had a higher effect on inhibiting the enzyme activity of Ba8a protein.Ba8a protein was relatively stable at pH 6.0 and temperature 0℃.It is indicated that the Bacillus subtilis SCUEC8 strain has the activity of α-amy-lase,which helps to improve the degradation rate of crop straw.关键词
α-淀粉酶/枯草芽孢杆菌SCUEC8菌株/ba8a基因/酶学特性Key words
α-amylase/Bacillus subtilis SCUEC8 strain/ba8a gene/enzymatic characteristics分类
农业科技引用本文复制引用
余振,徐玉荣,吴哲宽,张静怡,张小宇,俸婷,程国军,李晓华,饶雄飞..α-淀粉酶产生菌的筛选鉴定及Ba8a蛋白的酶学特性[J].华中农业大学学报,2025,44(4):143-149,7.基金项目
中国烟草总公司"雪茄烟叶开发与应用重大专项"揭榜棒挂帅项目(中烟办2022[111]号,110202201039(XJ-10)) （中烟办2022[111]号,110202201039(XJ-10）
国家自然科学基金项目(31070087,32372809) （31070087,32372809）
湖北省大学生创新创业训练计划项目(SCX2024066) （SCX2024066）
