Spectroscopic and magnetic studies of wild-type and mutant forms of the Fe(II)- and 2-oxoglutarate-dependent decarboxylase ALKBH4.

ABSTRACT: The Fe(II)/2OG (2-oxoglutarate)-dependent dioxygenase superfamily comprises proteins that couple substrate oxidation to decarboxylation of 2OG to succinate. A member of this class of mononuclear non-haem Fe proteins is the Escherichia coli DNA/RNA repair enzyme AlkB. In the present work, we describe the magnetic and optical properties of the yet uncharacterized human ALKBH4 (AlkB homologue). Through EPR and UV-visible spectroscopy studies, we address the Fe-binding environment of the proposed catalytic centre of wild-type ALKBH4 and an Fe(II)-binding mutant. We could observe a novel unusual Fe(III) high-spin EPR-active species in the presence of sulfide with a g(max) of 8.2. The Fe(II) site was probed with NO. An intact histidine-carboxylate site is necessary for productive Fe binding. We

SUBMITTER: Bjornstad LG 

PROVIDER: S-EPMC3048578 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature