Driving Protein Conformational Changes with Light: Photoinduced Structural Rearrangement in a Heterobimetallic Oxidase.

ABSTRACT: The heterobimetallic R2lox protein binds both manganese and iron ions in a site-selective fashion and activates oxygen, ultimately performing C-H bond oxidation to generate a tyrosine-valine cross-link near the active site. In this work, we demonstrate that, following assembly, R2lox undergoes photoinduced changes to the active site geometry and metal coordination motif. Through spectroscopic, structural, and mass spectrometric characterization, the photoconverted species is found to consist of a tyrosinate-bound iron center following light-induced decarboxylation of a coordinating glutamate residue and cleavage of the tyrosine-valine cross-link. This process occurs with high quantum efficiencies (Φ = 3%) using violet and near-ultraviolet light, suggesting that the photodecarboxylation is

SUBMITTER: Maugeri PT 

PROVIDER: S-EPMC6272062 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature