Expression and purification of a new esterase from metagenomic clone similar to bacterial esterase of the Porticoccus hydrocarbonoclasticus

Abstract

Esterases are lipolytic enzymes widely used in industrial applications. This work aimed the overexpression and purification of the esterase LipG7 identified from a metagenomic library constructed from mangrove sediments, which gene sequence shares 80% amino acid identity to 1,4-butanediol diacrylate esterase from the bacterium Porticoccus hydrocarbonoclasticus. LipG7 was expressed in three commercial Escherichia coli strains, Rosetta-gami, ArcticExpress and BL21 and the activity evaluated against 4-nitrophenyl butyrate substract. Recombinante esterase was obtained in soluble form only in Rosetta-gami after treatment with guanidine hydrochloride. It was active against 4-nitrophenyl butyrate at 30 °C with specific activity of 216.3 ± 16.4 U/mg that was significantly enhanced in presence of Mg2+ ion.