title: Identification of a halophilic α-amylase gene from Escherichia coli JM109 and characterization of the recombinant enzyme.
abstract: A halophilic α-amylase (EAMY) gene from Escherichia coli JM109 was overexpressed in E. coli XL10-Gold and the recombinant protein was purified and characterized. The activity of the EAMY depended on the presence of both Na(+) and Cl(-), and had maximum activity in 2 M NaCl at 55 °C and pH 7.0. When 2% (w/v) soluble starch was used as substrate, the specific activity was about 1,090 U mg(-1) protein. This is the first report on identifying a halophilic α-amylase with high specific activity from non-halophilic bacteria.
authors.affiliation: State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi University, Nanning, Guangxi, China. weiyutuo@gxu.edu.cn
authors.forename: Yutuo
authors.initials: Y
authors.lastname: Wei
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Wang
authors.forename: Jiayuan
authors.initials: J
authors.lastname: Liang
authors.forename: Xue
authors.initials: X
authors.lastname: Li
authors.forename: Liqin
authors.initials: L
authors.lastname: Du
authors.forename: Ribo
authors.initials: R
authors.lastname: Huang
mesh_terms: D002713:Chlorine / Q000378:metabolism; D003067:Coenzymes / Q000378:metabolism; D004795:Enzyme Stability; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D015870:Gene Expression; D006863:Hydrogen-Ion Concentration; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D012964:Sodium / Q000378:metabolism; D013213:Starch / Q000378:metabolism; D013696:Temperature; D000516:alpha-Amylases / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D003067:Coenzymes; D011994:Recombinant Proteins; D002713:Chlorine; D013213:Starch; D012964:Sodium; D000516:alpha-Amylases