Impact of distal mutation on hydrogen transfer interface and substrate conformation in soybean lipoxygenase.

ABSTRACT: The impact of distal mutation on the hydrogen transfer interface properties and on the substrate mobility, conformation, and orientation in soybean lipoxygenase-1 (SLO) is examined. SLO catalyzes a hydrogen abstraction reaction that occurs by a proton-coupled electron transfer mechanism. Mutation of isoleucine 553 to less bulky residues has been found experimentally to increase the magnitude and temperature dependence of the kinetic isotope effect for this reaction. This residue borders the linoleic acid substrate but is approximately 15 A from the active site iron. In the present study, we model these experimental data with a vibronically nonadiabatic theory and perform all-atom molecular dynamics simulations on the complete solvated wild-type and mutant enzymes. Our calculations indicate

SUBMITTER: Edwards SJ 

PROVIDER: S-EPMC2880924 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature