Mechanisms for Flavin-Mediated Oxidation: Hydride or Hydrogen-Atom Transfer?

Autor(es)

Curtolo, Felipe ^[1] ; Arantes, Guilherme M. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Quim, Dept Biochem, BR-05508900 Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF CHEMICAL INFORMATION AND MODELING; v. 60, n. 12, p. 6282-6287, DEC 28 2020.
• Citações Web of Science: 0

Resumo

Flavins are versatile biological cofactors which catalyze proton-coupled electron transfers (PCET) with varying number and coupling of electrons. Flavin-mediated oxidations of nicotinamide adenine dinucleotide (NADH) and of succinate, initial redox reactions in cellular respiration, were examined here with multiconfigurational quantum chemical calculations and a simple analysis of the wave function proposed to quantify electron transfer along the proton reaction coordinate. The mechanism of NADH oxidation is a prototypical hydride transfer, with two electrons moving concerted with the proton to the same acceptor group. However, succinate oxidation depends on the elimination step and can proceed through the transfer of a hydride or hydrogen atom, with proton and electrons moving to different groups in both cases. These results help to determine the mechanism of fundamental but still debated biochemical reactions and illustrate a new diagnostic tool for electron transfer that can be useful to characterize a broad class of PCET processes. (AU)

• Processo FAPESP: 16/23525-0 - Simulação computacional dos mecanismos de reação em quinol:fumarato redutases
• Beneficiário: Felipe Curtolo
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 16/24096-5 - Simulação computacional de metaloenzimas e de proteínas flexíveis
• Beneficiário: Guilherme Menegon Arantes
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 17/26109-0 - Simulação computacional de reatividade e transferência de elétrons no complexo II respiratório
• Beneficiário: Felipe Curtolo
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 19/21856-7 - Bioenergética molecular computacional
• Beneficiário: Guilherme Menegon Arantes
• Modalidade de apoio: Auxílio à Pesquisa - Regular