题 目：Biological methane oxidation 报告人：Amy C. Rosenzweig, Ph.D. Weinberg Family Distinguished Professor of Life Sciences, and Professor, Departments of Molecular Biosciences and of Chemistry, Northwestern University, Evanston NAS Member 地 点：太阳成集团仙林校区太阳集团tcy8722H201蒋雯若报告厅 时 间：2017年10月19日（周四）上午 10:00 邀请人：赵劲教授 Abstract: Methanotrophic bacteria oxidize methane to methanol in the first step of their metabolic pathway. Whereas current catalysts that can selectively activate the 105 kcal mol-1 C-H bond in methane require high temperatures and pressures, methanotrophs perform this chemistry under ambient conditions using methane monooxygenase (MMO) enzymes. In mostly all methanotrophs, this chemically challenging reaction is catalyzed by particulate methane monooxygenase (pMMO), a copper-dependent, integral membrane enzyme. Some methanotrophs can also produce an iron-containingm soluble methane monooxygenase (sMMO) under copper starvation conditions. In these strains, copper availability regulates which type of MMO is produced. pMMO is an integral membrane protein composed of three subunits, PmoA, PmoB, and PmoC, arranged in a trimeric complex. Despite extensive research and the availability of multiple crystal structures, the nature of the pMMO active site is controversial and the details of dioxygen activation and methane oxidation have not been elucidated. Mounting evidence points to a copper active site in the PmoB subunit, but the nuclearity and coordination of this site remain unresolved. Studies are further complicated by issues with retaining enzymatic activity and uncertainties regarding the identity of the native reductant and the possible involvement of additional proteins. Progress toward addressing these key questions will be reported. 配位化学国家重点实验室 太阳集团tcy8722 |