Expression and purification of organic solvent stable lipase from soil metagenomic library

• Published in: World journal of microbiology & biotechnology Vol. 28; no. 6; pp. 2417 - 2424
• Main Authors: Khan, Mahejibin, Jithesh, Kottur
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01-06-2012; Springer Nature B.V
• Subjects: Applied Microbiology; Binding sites; Biochemistry; Biomedical and Life Sciences; Biotechnology; Cations; Cloning; E coli; Environmental Engineering/Biotechnology; Enzyme Stability - drug effects; Enzymes; Gene expression; Gene Library; Genes; Genetic engineering; Genomics; Hydrogen-Ion Concentration; Life Sciences; Lipase - chemistry; Lipase - genetics; Lipase - isolation & purification; Lipase - metabolism; Metagenomics; Microbiology; Organic solvents; Original Paper; Soil; Soil microorganisms; Solvents; Solvents - pharmacology; Studies; Temperature; Xylene; Lipase; Metagenomic library; Enzyme stability
• ISSN: 0959-3993; 1573-0972
• DOI: 10.1007/s11274-012-1051-0

Gene for organic solvent stable lipase was overexpressed from soil metagenomic library. The clone with maximum activity was selected, and enzyme was purified by gel-permeation chromatography with a molecular mass of approx. 40 kDa. The deduced aminoacid sequence indicated that the protein belongs to the lipase family I.3 and containing a C-terminal secretion signal for ABC dependent transport together with possible motifs for Ca
2+
binding sites. The enzyme expressed maximum activity at 30 °C and pH 7.0 and found to be stable in pH and temperature ranging from 6.0–9.0 and 20–60 °C, respectively. Furthermore, the enzyme was found highly resistant to many organic solvents, especially isopropanol, DMSO, methanol, xylene and hexane. The enzyme showed enhanced activity in the presence of divalent cations (Mg
2+
, Mn
2+
, Ca
2+
, Hg
2+
, Cu
2+
), whereas the presence of trivalent cation (Fe
3+
) inhibited the activity.