Publicação
Determination of the active form of the tetranuclear copper sulfur cluster in nitrous oxide reductase
| Resumo: | N2OR has been found to have two structural forms of its tetranuclear copper active site, the 4CuS Cu-Z* form and the 4Cu2S Cu-Z form. EPR, resonance Raman, and MCD spectroscopies have been used to determine the redox states of these sites under different reductant conditions, showing that the Cu-Z* site accesses the 1-hole and fully reduced redox states, while the Cu-Z site accesses the 2-hole and 1-hole redox states. Single-turnover reactions of N2OR for Cu-Z and Cu-Z* poised in these redox states and steady-state turnover assays with different proportions of Cu-Z and Cu-Z* show that only fully reduced Cu-Z* is catalytically competent in rapid turnover with N2O. |
|---|---|
| Autores principais: | Johnston, Esther M. |
| Outros Autores: | Dell'Acqua, Simone; Ramos, Susana Jorge Guerreiro; Pauleta, Sofia Rocha; Moura, Isabel Maria Andrade Martins Galhardas de; Solomon, Edward I. |
| Assunto: | CU-Z CLUSTER ACHROMOBACTER-CYCLOCLASTES PSEUDOMONAS-NAUTICA CATALYTIC CENTER N2O REDUCTION PURIFICATION ENZYME RESONANCE MECHANISM INSIGHT |
| Ano: | 2014 |
| País: | Portugal |
| Tipo de documento: | artigo |
| Tipo de acesso: | acesso aberto |
| Instituição associada: | Universidade Nova de Lisboa |
| Idioma: | inglês |
| Origem: | Repositório Institucional da UNL |
| Resumo: | N2OR has been found to have two structural forms of its tetranuclear copper active site, the 4CuS Cu-Z* form and the 4Cu2S Cu-Z form. EPR, resonance Raman, and MCD spectroscopies have been used to determine the redox states of these sites under different reductant conditions, showing that the Cu-Z* site accesses the 1-hole and fully reduced redox states, while the Cu-Z site accesses the 2-hole and 1-hole redox states. Single-turnover reactions of N2OR for Cu-Z and Cu-Z* poised in these redox states and steady-state turnover assays with different proportions of Cu-Z and Cu-Z* show that only fully reduced Cu-Z* is catalytically competent in rapid turnover with N2O. |
|---|