Determination of the iron(IV) local spin states of the Q intermediate of soluble methane monooxygenase by Kβ X-ray emission spectroscopy.

ABSTRACT: Soluble methane monooxygenase (sMMO) facilitates the conversion of methane to methanol at a non-heme Fe^IV₂ intermediate MMOH_Q, which is formed in the active site of the sMMO hydroxylase component (MMOH) during the catalytic cycle. Other biological systems also employ high-valent Fe^IV sites in catalysis; however, MMOH_Q is unique as Nature's only identified Fe^IV₂ intermediate. Previous ⁵⁷Fe Mössbauer spectroscopic studies have shown that MMOH_Q employs antiferromagnetic coupling of the two Fe^IV sites to yield a diamagnetic cluster. Unfortunately, this lack of net spin prevents the determination of the local spin state (S_loc) of each of the irons by most spectroscopic techni

SUBMITTER: Cutsail GE 

PROVIDER: S-EPMC9470658 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature