A Morphing [4Fe‐3S‐nO]‐Cluster within a Carbon Monoxide Dehydrogenase Scaffold. Issue 18 (4th March 2022)

• Record Type: Journal Article
• Authors: Jeoung, Jae‐Hun; Fesseler, Jochen; Domnik, Lilith; Klemke, Friederike; Sinnreich, Malte; Teutloff, Christian; Dobbek, Holger
• Is Part Of: Angewandte Chemie international edition. Volume 61:Issue 18(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-03-04
• Subjects: CODH Evolution -- Enzymes -- Hydroxylamine Reduction -- Iron-Sulfur-Oxo Cluster -- Structural Biology; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.202117000
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Ni, Fe‐containing carbon monoxide dehydrogenases (CODHs) catalyze the reversible reduction of CO2 to CO. Several anaerobic microorganisms encode multiple CODHs in their genome, of which some, despite being annotated as CODHs, lack a cysteine of the canonical binding motif for the active site Ni, Fe‐cluster. Here, we report on the structure and reactivity of such a deviant enzyme, termed CooS‐VCh . Its structure reveals the typical CODH scaffold, but contains an iron‐sulfur‐oxo hybrid‐cluster. Although closely related to true CODHs, CooS‐VCh catalyzes neither CO oxidation, nor CO2 reduction. The active site of CooS‐VCh undergoes a redox‐dependent restructuring between a reduced [4Fe‐3S]‐cluster and an oxidized [4Fe‐2S‐S*‐2O‐2(H2 O)]‐cluster. Hydroxylamine, a slow‐turnover substrate of CooS‐VCh, oxidizes the hybrid‐cluster in two structurally distinct steps. Overall, minor changes in CODHs are sufficient to accommodate a Fe/S/O‐cluster in place of the Ni, Fe‐heterocubane‐cluster of CODHs. Abstract : The exchange of one amino acid (Cys‐>Glu) coordinating the Ni/Fe/S‐cluster in carbon monoxide dehydrogenases (CODH) is the main difference resulting in the formation of a Fe/S/O‐hybrid‐cluster, found in CooS‐V, while conserving the overall architecture of CODHs. The Fe/S/O‐hybrid‐cluster in CooS‐V reversibly rearranges dependent on its redox‐state.