一株产酸性α-淀粉酶菌株的筛选、纯化及酶学性质  

Isolation and Purification of a Strain Producing Acid α-amylase and Its Enzamatic Characterization

作　　者：谢建华[1,2] 师永生[1,2] 杜丽琴[1,2] 黄日波[1,2] 韦宇拓[1,2] 

机构地区：[1]广西大学生命科学与技术学院,南宁530005 [2]广西亚热带生物资源保护利用重点实验室,南宁530005

出　　处：《应用与环境生物学报》2011年第1期95-99,共5页Chinese Journal of Applied and Environmental Biology

基　　金：国家"863"项目(No.2006AA020204)资助~~

摘　　要：从南宁酒厂附近土壤中筛选到一株产淀粉酶的野生菌株GXBA-4,经革兰氏染色、芽孢染色以及16SrDNA鉴定,初步确定为解淀粉芽孢杆菌（Bacillus amyloliquefacien）.将该菌株发酵液经过硫酸铵沉淀和凝胶过滤纯化出一种α-淀粉酶,该酶相对分子质量约为57×103;反应最适温度为40~45℃,适应温度范围广,30℃时仍具有80%以上的相对活力;最适pH为5.0,为低温酸性淀粉酶.该酶水解可溶性淀粉的产物,经HPLC检测主要是以葡萄糖,麦芽糖以及麦芽三糖为主的低聚糖,分别以α-环糊精、β-环糊精、可溶性淀粉、玉米生淀粉为底物,还原糖产物比为0：0：99：3.4,表明该酶为典型的α-淀粉酶.An acid α-amylase producing strain,named as GXBA-4,was isolated from the soil close to a distillery in Nanning,Guangxi,China.It was initially identified as Bacillus amyloliquefaciens with Gram straining,gemma straining and 16S rDNA analysis.The acid α-amylase was purified from the crude enzyme after ammonium sulfate precipitation and gel filtration.The molecular weight of the purified α-amylase was about 57×103.The optimum temperature and pH of the α-amylase were 40~45 ℃ and 5.0,respectively.The results of HPLC showed that the hydrolysis products of soluble starch catalyzed by the enzyme were oligosaccharides containing glucose,maltose and maltotriose.The ratio of their reducing products was 0 ： 0 ： 99 ： 3.4 using α-cyclodextrin,β-cyclodextrin,soluble starch and corn starch as substrates,respectively.The enzyme is classified as a typical α-amylase.

关 键 词：芽孢杆菌 酸性淀粉酶 纯化 酶学性质 

分 类 号：TQ925[轻工技术与工程—发酵工程]