Overexpression and characterization of a new organic solvent-tolerant esterase derived from soil metagenomic DNA

• Published in: Bioresource technology Vol. 116; pp. 234 - 240
• Main Authors: Jin, Peng, Pei, Xiaolin, Du, Pengfei, Yin, Xiaopu, Xiong, Xiaolong, Wu, Huili, Zhou, Xiuling, Wang, Qiuyan
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.07.2012
• Subjects: Adaptation, Physiological - drug effects; Alkanes; Amino Acid Sequence; Benzene; Chromatography, Thin Layer; Cloning, Molecular; DNA - metabolism; Enzyme Stability - drug effects; Enzymes; Escherichia coli; Esterases; Esterases - chemistry; Esterases - genetics; Esterases - isolation & purification; Esterases - metabolism; Esters; Hydrogen-Ion Concentration - drug effects; Metagenomic esterase; Metagenomics; Molecular Sequence Data; Organic Chemicals - pharmacology; Organic solvents tolerance; Phylogeny; Proteins; Sequence Alignment; Sequence Analysis, DNA; Soil (material); Soil - chemistry; Soil Microbiology; Solvents - pharmacology; Substrate Specificity - drug effects; Organic solvents tolerance; Metagenomic esterase
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2011.10.087

► A metagenome-derived esterase was cloned and overexpressed in Escherichia coli. ► High expression level constituted about 30% of the total cell protein was achieved. ► The enzyme has maximal activity at 40°C and maintains 50% its activity at 5–10°C. ► The enzyme is highly resistant to organic solvents with high logP. ► The enzyme has ability to cleave esters of tertiary alcohols. In this study, an esterase, designated EstC23, was isolated from a soil metagenomic library. The protein was amenable to overexpression in Escherichia coli under control of the T7 promoter, resulting in expression of the active, soluble protein that constituted 30% of the total cell protein content. This enzyme showed optimal activity at 40°C and retained about 50% maximal activity at 5–10°C. EstC23 showed remarkable stability in up to 50% (v/v) benzene and alkanes (high logP solvents). When incubated for 7days in the presence of 50% benzene or alkanes, the enzyme maintained its 2–3 fold elevated activity. The purified enzyme also cleaved sterically hindered esters of tertiary alcohols. These results indicate that EstC23 has potential for use in industrial processes.