8X9E

Crystal structure of CO dehydrogenase mutant with increased affinity for electron mediators in low PEG concentration

Summary for 8X9E

• Entry DOI: 10.2210/pdb8x9e/pdb
• Descriptor: Carbon monoxide dehydrogenase 2, IRON/SULFUR CLUSTER, FE2/S2 (INORGANIC) CLUSTER, ... (7 entities in total)
• Functional Keywords: electron transport, oxidoreductase
• Biological source: Carboxydothermus hydrogenoformans Z-2901
• Total number of polymer chains: 1
• Total formula weight: 70118.50

Authors

Lee, H.H.,Heo, Y.,Yoon, H.J.,Kim, S.M.,Kong, S.Y. (deposition date: 2023-11-30, release date: 2024-04-17, Last modification date: 2024-05-08)

Primary citation

Kim, S.M.,Kang, S.H.,Lee, J.,Heo, Y.,Poloniataki, E.G.,Kang, J.,Yoon, H.J.,Kong, S.Y.,Yun, Y.,Kim, H.,Ryu, J.,Lee, H.H.,Kim, Y.H.
Identifying a key spot for electron mediator-interaction to tailor CO dehydrogenase's affinity.
Nat Commun, 15:2732-2732, 2024

PubMed Abstract: Fe‒S cluster-harboring enzymes, such as carbon monoxide dehydrogenases (CODH), employ sophisticated artificial electron mediators like viologens to serve as potent biocatalysts capable of cleaning-up industrial off-gases at stunning reaction rates. Unraveling the interplay between these enzymes and their associated mediators is essential for improving the efficiency of CODHs. Here we show the electron mediator-interaction site on ChCODHs (Ch, Carboxydothermus hydrogenoformans) using a systematic approach that leverages the viologen-reactive characteristics of superficial aromatic residues. By enhancing mediator-interaction (R57G/N59L) near the D-cluster, the strategically tailored variants exhibit a ten-fold increase in ethyl viologen affinity relative to the wild-type without sacrificing the turn-over rate (k). Viologen-complexed structures reveal the pivotal positions of surface phenylalanine residues, serving as external conduits for the D-cluster to/from viologen. One variant (R57G/N59L/A559W) can treat a broad spectrum of waste gases (from steel-process and plastic-gasification) containing O. Decoding mediator interactions will facilitate the development of industrially high-efficient biocatalysts encompassing gas-utilizing enzymes.

PubMed: 38548760
DOI: 10.1038/s41467-024-46909-1

Experimental method

X-RAY DIFFRACTION (2.5 Å)