Crystallographic Investigation of Imidazolium Ionic Liquid Effects on Enzyme Structure.

ABSTRACT: We present the first crystallographic insight into the interactions of an ionic liquid (IL) with an enzyme, which has widespread implications for stabilizing enzymes in IL media for biocatalysis. Structures of Bacillus subtilis lipase A (lipA) and an IL-stable variant (QM-lipA) were obtained in the presence of increasing concentrations of 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]). These studies revealed that the [BMIM] cation interacts with surface residues through hydrophobic and cation-π interactions. Of specific interest was the disruption of internal stacking interactions of aromatic side chains by [BMIM], which provides structural evidence for the mechanism of enzyme denaturation by ILs. The interaction of [BMIM] and Cl ions with lipA was reduced by the stabilizing mutations Y

SUBMITTER: Nordwald EM 

PROVIDER: S-EPMC4827357 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature