REAL

Molecular cloning and characterization of a thermostable esterase/lipase produced by a novel Anoxybacillus flavithermus strain

Chiş, L. and Hriscu, M. and Bica, A. and Nagy, Gergely and Róna, Gergely and Vértessy G., Beáta (2013) Molecular cloning and characterization of a thermostable esterase/lipase produced by a novel Anoxybacillus flavithermus strain. JOURNAL OF GENERAL AND APPLIED MICROBIOLOGY, 59 (2). pp. 119-134. ISSN 0022-1260

[img]
Preview
Text
JGenApplMicrobiol2013Chis.pdf

Download (977kB) | Preview

Abstract

A thermophilic strain producing an extracellular esterase/lipase was isolated from a hot spring in Tǎşnad, Romania, and was identified phenotypically and by 16S rDNA sequencing as Anoxybacillus flavithermus (GenBank ID: JQ267733). The gene encoding the putative carboxyl esterase (GenBank ID: JX494348) was cloned by direct PCR amplification from genomic DNA. The protein, consisting of 246 amino acids and having a predicted molecular weight of 28.03 kDa, is encoded by an ORF of 741 bps. Expression was achieved in Escherichia coli and a recombinant protein with esterolytic activity and estimated molecular weight of 25 kDa was recovered and purified from the periplasmic fraction by IMAC. The purified enzyme, most active at 60-65°C and in the near-neutral range (pH 6.5-8), displayed a half-life at 60°C of about 5 h. Est/Lip displayed a relative tolerance to methanol, DMSO, acetonitrile, and low detergent concentrations (SDS, Triton) increased its thermostability. Highest activity was attained with p-nitrophenyl butyrate, but the enzyme was also able to hydrolyze long chain fatty acid esters, as well as triolein. The primary sequence and predicted tridimensional structure of the enzyme are very similar to those of other Anoxybacillus and Geobacillus carboxyl esterases in a distinct, recently described lipase family. Est/Lip was highly enantioselective, with preference for the (S)-enantiomer of substrates.

Item Type: Article
Uncontrolled Keywords: Tridimensional structure; Thermostable esterase/lipase; Gene cloning and expression; ENANTIOSELECTIVITY; Biochemical characterization; Anoxybacillus flavithermus
Subjects: Q Science / természettudomány > QH Natural history / természetrajz > QH301 Biology / biológia > QH3011 Biochemistry / biokémia
Q Science / természettudomány > QH Natural history / természetrajz > QH301 Biology / biológia > QH3015 Molecular biology / molekuláris biológia
SWORD Depositor: MTMT SWORD
Depositing User: MTMT SWORD
Date Deposited: 06 Jul 2013 08:40
Last Modified: 17 Oct 2013 12:25
URI: http://real.mtak.hu/id/eprint/5828

Actions (login required)

Edit Item Edit Item