Increased activity of enzymatic transacylation of acrylates through rational design of lipases

• A rational design approach was used to create the mutant Candida antarctica lipase B (CALB, also known as Pseudozyma antarctica lipase B) V190A having a k(cat) three times higher compared to that of the wild type (wt) enzyme for the transacylation of the industrially important compound methyl methacrylate. The enzymatic contribution to the transacylation of various acrylates and corresponding saturated esters was evaluated by comparing the reaction catalysed by CALB wt with the acid (H2SO4) catalysed reaction. The performances of CALB wt and mutants were compared to two other hydrolases, Humicola insolens cutinase and Rhizomucor mihei lipase. The low reaction rates of enzyme catalysed transacylation of acrylates were found to be caused mainly by electronic effects due to the double bond present in this class of molecules. The reduction in rate of enzyme catalysed transacylation of acrylates compared to that of the saturated ester methyl propionate was however less than what could be predicted from the energetic cost of breaking the pi-system of acrylates solely. The nature and concentration of the acyl acceptor was found to have a profound effect on the reaction rate. (C) 2009 Elsevier B.V. All rights reserved.

Ämnesord

NATURVETENSKAP  -- Biologi -- Biokemi och molekylärbiologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences -- Biochemistry and Molecular Biology (hsv//eng)

NATURVETENSKAP  -- Kemi -- Fysikalisk kemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences -- Physical Chemistry (hsv//eng)

Nyckelord

Lipase

CALB

Point mutations

Kinetics

Proficiency

Biochemistry

Biokemi

Molecular biology

Molekylärbiologi

Physical chemistry

Fysikalisk kemi

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)