Events

*Postponed*

Life Depends on Metal Oxos

Presented by Prof. Harry Gray
Hosted by Prof. Parkin

Abstract:
High-valent metal-oxos are reactive intermediates in three of the most important chemical reactions on planet Earth: water oxidation to oxygen in photosystem II; oxygen reduction to water in cytochrome oxidase; and hydrocarbon oxygenation catalyzed by cytochrome P450. To prevent oxidative destruction of P450 during uncoupled turnover, Jay Winkler and I have suggested that intermediate iron-oxo oxidants are reduced by hole transfer to Trp/Tyr chains extending from the heme active site to the enzyme surface. Measurements of activities and total turnover numbers for reactions of P450 BM3 and selected mutants support the proposed hole hopping protective mechanism.