7ZKV

F231A variant of the CODH/ACS complex of C. hydrogenoformans

Summary for 7ZKV

• Entry DOI: 10.2210/pdb7zkv/pdb
• Descriptor: Carbon monoxide dehydrogenase, CO-methylating acetyl-CoA synthase, Fe(3)-Ni(1)-S(4) cluster, ... (10 entities in total)
• Functional Keywords: co2 reduction, acetyl-coa synthesis, carbon monoxide, oxidoreductase
• Biological source: Carboxydothermus hydrogenoformans Z-2901; More
• Total number of polymer chains: 2
• Total formula weight: 157142.21

Authors

Ruickoldt, J.,Jeoung, J.-H.,Basak, Y.,Domnik, L.,Dobbek, H. (deposition date: 2022-04-13, release date: 2022-11-02, Last modification date: 2024-06-19)

Primary citation

Ruickoldt, J.,Jeoung, J.H.,Rudolph, M.A.,Lennartz, F.,Kreibich, J.,Schomacker, R.,Dobbek, H.
Coupling CO2 Reduction and Acetyl-CoA Formation: The Role of a CO Capturing Tunnel in Enzymatic Catalysis.
Angew.Chem.Int.Ed.Engl., :e202405120-e202405120, 2024

PubMed Abstract: The bifunctional CO-dehydrogenase/acetyl-CoA synthase (CODH/ACS) complex couples the reduction of CO2 to the condensation of CO with a methyl-moiety and CoA to acetyl-CoA. Catalysis occurs at two sites connected by a tunnel transporting the CO. Here, we investigated how the bifunctional complex and its tunnel support catalysis using the CODH/ACS from Carboxydothermus hydrogenoformans as a model. Although CODH/ACS adapted to form a stable bifunctional complex with a secluded substrate tunnel, catalysis and CO transport is even more efficient when two monofunctional enzymes are coupled. Efficient CO channeling appears to be ensured by hydrophobic binding sites for CO, which act in a bucket-brigade fashion rather than as a simple tube. Tunnel remodeling showed that opening the tunnel increased activity but impaired directed transport of CO. Constricting the tunnel impaired activity and CO transport, suggesting that the tunnel evolved to sequester CO rather than to maximize turnover.

PubMed: 38743001
DOI: 10.1002/anie.202405120

Experimental method

X-RAY DIFFRACTION (2.066 Å)