Can Water Act as a Nucleophile in CO Oxidation Catalysed by Mo/Cu CO-Dehydrogenase? Answers from Theory

The aerobic CO dehydrogenase from Oligotropha carboxidovorans is an environmentally crucial bacterial enzyme for maintenance of subtoxic concentration of CO in the lower atmosphere, as it allows for the oxidation of CO to CO2 which takes place at its Mo−Cu heterobimetallic active site. Despite extensive experimental and theoretical efforts, significant uncertainties still concern the reaction mechanism for the CO oxidation. In this work, we used the hybrid quantum mechanical/molecular mechanical approach to evaluate whether a water molecule present in the active site might act as a nucleophile upon formation of the new C−O bond, a hypothesis recently suggested in the literature. Our study shows that activation of H2O can be favoured by the presence of the Mo=Oeq group. However, overall our results suggest that mechanisms other than the nucleophilic attack by Mo=Oeq to the activated carbon of the CO substrate are not likely to constitute reactive channels for the oxidation of CO by the enzyme.

Moro, GiorgioUniversity of Milano-Bicocca (författare)
Cosentino, UgoUniversity of Milano-Bicocca (författare)
Ryde, UlfLund University,Lunds universitet,Beräkningskemi,Enheten för fysikalisk och teoretisk kemi,Kemiska institutionen,Institutioner vid LTH,Lunds Tekniska Högskola,Computational Chemistry,Physical and theoretical chemistry,Department of Chemistry,Departments at LTH,Faculty of Engineering, LTH(Swepub:lu)teok-ury (författare)
Greco, ClaudioUniversity of Milano-Bicocca(Swepub:lu)teok-cgc (författare)
University of Milano-BicoccaBeräkningskemi (creator_code:org_t)

Av författaren/redakt...: Rovaletti, Anna; Moro, Giorgio; Cosentino, Ugo; Ryde, Ulf; Greco, Claudio

Om ämnet

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.