福州大学学报（自然科学版）2018，Vol.46Issue(1)：143-150,8.DOI:10.7631/issn.1000-2243.16346
温泉来源地芽孢杆菌耐热α-淀粉酶基因的克隆表达及酶学性质研究
Cloning, expression and characterization of the thermostable alpha-amylase gene from Geobacillus sp.WQJ-1 isolated from hot springs
摘要
Abstract
The amy WQJ gene encoding alpha-amylase from Geobacillus sp.WQJ-1 was amplified by PCR,and linked with vector pET-28a (+).The constructed recombinant plasmid pET-28a (+)-amyWQJ was transformed into E.coli BL21 (DE3),and the recombinant protein was obtained via induction of expression and purified by nickel affinity chromatography,the purified enzyme presented as one protein band on SDS-PAGE with molecular weight of 59 ku.The study showed that the optimum pH value was 6.0,and it has good pH stability,optimum temperature of purified alpha-amylase was 70 ℃C.Ca2+can significantly improve the thermostability of the enzyme.The activity of the enzyme was inhibited by Hg2+,EDTA,SDS,Cr3+,Mn2+,Cu2+ and Pb2+in different degrees,and activated by Co2+,Na+andβ-Mercaptoethanol.By using starch soluble as substrate,the Km was 6.62 mg · mL-1 and vmax was 2 197.80 μmol · (mg · min)-1.Oligosaccharide is the final product of enzymatic hydrolysis of Starch cassava.关键词
地芽孢杆菌/α-淀粉酶/克隆/表达/酶学性质Key words
Geobacillus/alpha-amylase/cloning/expression/characterization分类
生物科学引用本文复制引用
林云,林娟,王国增,林梦丹,叶秀云..温泉来源地芽孢杆菌耐热α-淀粉酶基因的克隆表达及酶学性质研究[J].福州大学学报（自然科学版）,2018,46(1):143-150,8.基金项目
国家863计划资助项目(2013AA102101) （2013AA102101）
