Improved enantioselectivity of a lipase by rational protein engineering
2001 (English)In: ChemBioChem (Print), ISSN 1439-4227, E-ISSN 1439-7633, Vol. 2, no 10, 766-770 p.Article in journal (Refereed) Published
A model based on two different binding modes for alcohol enantiomers in the active site of a lipase allowed rational redesign of its enantioselectivity, 1-Halo-2-octanols were poorly resolved by Candida antarctica lipase B. Interactions between the substrates and the lipase were investigated with molecular modeling. Unfavorable interactions were found between the halogen moiety of the fast-reacting S enantiomer and a region situated at the bottom of the active site (stereoselectivity pocket). The lipase was virtually mutated in this region and energy contour maps of some variants displayed better interactions for the target substrates. Four selected variants of the lipase were produced and kinetic resolution experiments were undertaken with these mutants. Single point mutants gave rise to one variant with doubled enantioselectivity as well as one variant with annihilated enantioselectivity towards the target halohydrins. An increased volume of the stereoselectivity pocket caused a decrease in enantioselectivity, while changes in electrostatic potential increased enantioselectivity, The enantioselectivity of these new lipase variants towards other types of alcohols was also investigated. The changes in enantioselectivity caused by the mutations were well in agreement with the proposed model concerning the chiral recognition of alcohol enantiomers by this lipase.
Place, publisher, year, edition, pages
2001. Vol. 2, no 10, 766-770 p.
enzyme catalysis, kinetic resolution, lipases, protein engineering, rational design, candida-antarctica, directed evolution, alcohol enantiomers, fine chemicals, biocatalysis, recognition, esterase, creation
IdentifiersURN: urn:nbn:se:kth:diva-20994ISI: 000171410000007OAI: oai:DiVA.org:kth-20994DiVA: diva2:339691
QC 201005252010-08-102010-08-10Bibliographically approved