A theoretical study on the reactivity of the Mo/Cu-containing carbon monoxide dehydrogenase with dihydrogen

作者：Breglia Raffaella; Bruschi Maurizio; Cosentino Ugo; De Gioia Luca; Greco Claudio^*; Miyake Toshiko; Moro Giorgio

来源：Protein Engineering Design and Selection, 2017, 30(3): 169-174.

DOI：10.1093/protein/gzw071

• carbon monoxide dehydrogenase
• density functional theory
• hydrogenase
• molecular hydrogen

The Mo/Cu-dependent CO dehydrogenase from Oligotropha carboxidovorans is an enzyme that is able to catalyze CO oxidation to CO2; moreover, it can also oxidize H-2, thus eliciting a characteristic EPR signal. Interestingly, the Ag-substituted enzyme form proved unable to catalyze H-2 oxidation. In the present contribution, we characterized the reactivity of the enzyme with H-2 by quantum-chemical calculations. It was found that dihydrogen binding to the wild-type enzyme requires significant structural rearrangements of the active site Theoretical EPR spectra for plausible H-2-bound models of the partially reduced, paramagnetic active site are also presented and compared with the experimental counterpart. Finally, density functional theory modeling shows that Ag substitution impairs H-2 binding at the active site.

• 出版日期2017-3