Geometric and electronic structure of the Mn(IV)Fe(III) cofactor in class Ic ribonucleotide reductase: correlation to the class Ia binuclear non-heme iron enzyme.

ABSTRACT: The class Ic ribonucleotide reductase (RNR) from Chlamydia trachomatis (Ct) utilizes a Mn/Fe heterobinuclear cofactor, rather than the Fe/Fe cofactor found in the β (R2) subunit of the class Ia enzymes, to react with O2. This reaction produces a stable Mn(IV)Fe(III) cofactor that initiates a radical, which transfers to the adjacent α (R1) subunit and reacts with the substrate. We have studied the Mn(IV)Fe(III) cofactor using nuclear resonance vibrational spectroscopy (NRVS) and absorption (Abs)/circular dichroism (CD)/magnetic CD (MCD)/variable temperature, variable field (VTVH) MCD spectroscopies to obtain detailed insight into its geometric/electronic structure and to correlate structure with reactivity; NRVS focuses on the Fe(III), whereas MCD reflects the spin-allowed transitions mostl

SUBMITTER: Kwak Y 

PROVIDER: S-EPMC3882272 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature