Molecular Characterization of a Novel Arylesterase from the Wine-Associated Acetic Acid Bacterium Gluconobacter oxidans 621H
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- 作者：Inmaculada Navarro-Gonz谩lez ; 脕lvaro S谩nchez-Ferrer ; Francisco Garc铆a-Carmona
- 刊名：Journal of Agricultural and Food Chemistry
- 出版年：2012
- 出版时间：October 31, 2012
- 年：2012
- 卷：60
- 期：43
- 页码：10789-10795
- 全文大小：425K
- 年卷期：v.60,no.43(October 31, 2012)
- ISSN：1520-5118
文摘
An arylesterase from the wine-making acetic acid bacterium, Gluconobacter oxidans, was cloned and expressed into Escherichia coli. The soluble 76.8 kDa dimeric enzyme obtained, Est0881, was purified in only two steps with a 3.1-fold purification, 43% recovery, and a specific activity of 214 U/mg for the hydrolysis of p-nitrophenyl acetate. The optimum pH and temperature were 7.0 and 40 掳C, respectively. The substrate specificity of this arylesterase was higher toward short chain p-nitrophenyl esters (C2 to C4) and also toward aromatic esters, such as phenyl acetate. The deduced amino acid sequence shares high identity with esterases of the HSL family. The inhibition results obtained showed that the enzyme was a serine esterase, belonging to the A-esterases (arylesterases) and contains a catalytic triad composed of Ser163, Asp263, and His293 in the active site. Est0881 retained significant activity under conditions simulating those of wine-making (75% activity at 20% ethanol), making it a promising biocatalyst for modulating the final aroma of wine.