Rice (Oryza sativa) lipase: Molecular cloning, functional expression and substrate specificity.

Vijayakumar, K. R. and Lalitha, R. Gowda (2013) Rice (Oryza sativa) lipase: Molecular cloning, functional expression and substrate specificity. Protein Expression and Purification, 88. pp. 67-79.

PDF Protein Expression and Purification, Volume 88, Issue 1, March 2013, Pages 67-79.pdf - Published Version Restricted to Registered users only Download (2MB)

Abstract

Lipases are important biocatalysts showing many interesting properties with industrial applications. Previously, different isoforms of lipases, Lipase-I and Lipase-II from rice (Oryza sativa) have been purified and characterized. Lipase-II identified as the major lipase in rice bran is designated as rice bran lipase (RBL). In this study, we report the cloning and expression of the RBL in Escherichia coli and Pichia pastoris. An exploration of expression in four different E. coli expression systems analyzed: BL21(DE3)pLysS, RIL(DE3)pLysS, Rosetta(DE3)pLysS and Origami(DE3)pLysS indicated that E. coli was not a suitable host. Expression with supplement of rare codons in Rosetta (DE3)pLysS and RIL(DE3)pLysS resulted in highest expression as insoluble inclusion bodies. The hurdles of expression in E. coli were overcome by expression as a secretory protein in P. pastoris X-33. The expression of lipase in shake flasks was optimized to achieve the maximum recombinant lipase activity of 152.6 U/mL. The purified recombinant lipase had a specific activity of 998 U/mg toward triacetin. The pH and temperature optimum of native and recombinant enzymes were pH 7.4 and 25 ± 2 �C, respectively. Both the lipases showed higher activity toward short chain triacylglycerol and unsaturated fatty acid enriched oils. Computational modeling and molecular docking studies reveal that the catalytic efficiency of the lipase correlates with the distance of the nucleophilic Ser175-OH and the scissile ester bond. The shorter the distance, the greater is the turnover of the substrate.

Item Type:	Article
Uncontrolled Keywords:	Cloning, Expression, Lipase, Molecular docking Pichia pastoris
Subjects:	500 Natural Sciences and Mathematics > 04 Chemistry and Allied Sciences > 29 Protein Chemistry 600 Technology > 08 Food technology > 21 Cereals > 01 Rice
Divisions:	Protein Chemistry and Technology
Depositing User:	Food Sci. & Technol. Information Services
Date Deposited:	11 Feb 2013 06:47
Last Modified:	11 Feb 2013 06:47
URI:	http://ir.cftri.res.in/id/eprint/11116

Actions (login required)

View Item