title: Characterization of a novel cold active and salt tolerant esterase from Zunongwangia profunda.
abstract: A novel cold active esterase, EstLiu was cloned from the marine bacterium Zunongwangia profunda, overexpressed in E. coli BL21 (DE3) and purified by glutathione-S transferase (GST) affinity chromatography. The mature esterase EstLiu sequence encodes a protein of 273 amino acids residues, with a predicted molecular weight of 30KDa and containing the classical pentapeptidase motif from position 156 to 160 with the catalytic triad Ser158-Asp211-His243. Although, EstLiu showed 64% similarity with the hypothetical esterase from Chryseobacterium sp. StRB126 (WP_045498424), phylogenetic analysis showed it had no similarity with any of the established family of lipases/esterases, suggesting that it could be considered as a new family. The purified enzyme showed broad substrate specificity with the highest hydrolytic activity against p-nitrophenyl butyrate (C4). EstLiu showed remarkable activity (75%) at 0°Cand the optimal activity at pH 8.0 and 30°C with good thermostability and quickened inactivation above 60°C. EstLiu retained 81, 103, 67 and 78% of its original activity at 50% (v/v) in ethanol, isopropanol, DMSO and ethylene glycol, respectively. In the presence of Tween 20, Tween 80 and Triton X-100, EstLiu showed 88, 100 and 117% of relative activity. It is also co-factor independent. The high activity at low temperature and desirable stability in organic solvents and salts of this novel family esterase represents a good evidence of novel biocatalyst. Overall, this novel enzyme showed better activity than previously reported esterases in extreme reaction conditions and could promote the reaction in both aqueous and non-aqueous conditions, indicating its great potential for industrial applications.
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China. Electronic address: nayongeb@gmail.com.
authors.forename: Mohammad Asadur
authors.initials: MA
authors.lastname: Rahman
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China. Electronic address: eshageb@gmail.com.
authors.forename: Umma
authors.initials: U
authors.lastname: Culsum
authors.affiliation: Hubei Vocational College of Bio-technology, Wuhan 430070, People's Republic of China. Electronic address: 530278919@qq.com.
authors.forename: Wenhao
authors.initials: W
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China. Electronic address: zhangzhsw@163.com.
authors.forename: Shao Wei
authors.initials: SW
authors.lastname: Zhang
authors.affiliation: College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China. Electronic address: wgb@mail.hzau.edu.cn.
authors.forename: Gaobing
authors.initials: G
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, People's Republic of China. Electronic address: Lzd308@yahoo.cn.
authors.forename: Ziduo
authors.initials: Z
authors.lastname: Liu
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D003080:Cold Temperature; D004795:Enzyme Stability; D004950:Esterases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D041965:Flavobacteriaceae / Q000201:enzymology* / Q000235:genetics; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008958:Models, Molecular; D010802:Phylogeny; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D054712:Salinity; D016415:Sequence Alignment; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D011994:Recombinant Proteins; D004950:Esterases
keywords: Cold-active; Novel esterase; Organic solvent tolerant; Salt tolerant