Designing O2-tolerant hydrogenases is a major challenge in applying [Fe-Fe] H2ases for large scale H2 production. The kinetics of inhibition could be derived by a two-step model, where there is first transport of oxygen from the external medium through the enzyme (depending on the gas tunnel) to a non-coordinating site close to the H-cluster, followed by the deactivation of the active site. To explore the nature of the oxygen channel for the hydrogenases from Desulfovibrio desulfuricans (DdH) and Clostridium pasteurianum (CpI), MD simulations using the CHARMM force field were performed, suggesting selected mutations for reducing oxygen's access, as will be discussed. In addition, for elucidating the mechanism of oxygen inhibition within H-cluster of the [Fe-Fe] hydrogenase, in comparison with experimentally based suppositions, density functional theory calculations of model compounds composed of the H-cluster and proximate amino acids will be reported.

Oxygen inhibition of the biocatalysis in [Fe-Fe] hydrogenases: A combination of empirical molecular dynamics and density functional theory calculations

243rd National Meeting (2012)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.