title: Chemical Plausibility of Cu(III) with Biological Ligation in pMMO.
abstract: The mechanisms of dioxygen activation and methane C-H oxidation in particulate methane monooxygenase (pMMO) are currently unknown. Recent studies support a binuclear copper site as the catalytic center. We report the low-temperature assembly of a high-valent dicopper(III) bis(μ-oxide) complex bearing marked structural fidelity to the proposed active site of pMMO. This unprecedented dioxygen-bonded Cu(III) species with exclusive biological ligation directly informs on the chemical plausibility and thermodynamic stability of the bis(μ-oxide) structure in such dicopper sites and foretells unusual optical signatures of an oxygenation product in pMMO. Though the ultimate pMMO active oxidant is still debated, C-H oxidation of exogenous substrates is observed with the reported Cu(III) complexes. The assembly of a high valent species both narrows the search for relevant pMMO intermediates and provides evidence to substantiate the role of Cu(III) in biological redox processes.
authors.affiliation: †Department of Chemistry, Stanford University, Stanford, California 94305, United States.
authors.forename: Cooper
authors.initials: C
authors.lastname: Citek
authors.affiliation: †Department of Chemistry, Stanford University, Stanford, California 94305, United States.
authors.forename: J Brannon
authors.initials: JB
authors.lastname: Gary
authors.affiliation: ‡Department of Chemistry and Biochemistry, California State University, Chico, California 95929, United States.
authors.forename: Erik C
authors.initials: EC
authors.lastname: Wasinger
authors.affiliation: †Department of Chemistry, Stanford University, Stanford, California 94305, United States.
authors.forename: T Daniel P
authors.initials: TD
authors.lastname: Stack
mesh_terms: D003300:Copper / Q000737:chemistry / Q000378:metabolism*; D010105:Oxygenases / Q000737:chemistry / Q000378:metabolism*; D013816:Thermodynamics
chemical_list: D003300:Copper; D010105:Oxygenases; C021555:methane monooxygenase