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Updated: Aug 14, 2026
09:58
Light-driven Enzymatic Decarboxylation
Published on: May 22, 2016
Carbon monoxide dehydrogenase from Rhodospirillum rubrum produces formate
Jongyun Heo1, Lars Skjeldal, Christopher R Staples
1Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin-Madison, 53706-1544, USA.
Summary
Carbon monoxide dehydrogenase (CODH) catalyzes CO oxidation. This study reveals CODH also slowly reduces CO(2) to formate, a side reaction occurring with or without the active site’s nickel (Ni) component.
Area of Science:
- Biochemistry
- Enzyme catalysis
- Bioinorganic chemistry
Background:
- Carbon monoxide dehydrogenase (CODH) from Rhodospirillum rubrum is known to reversibly catalyze CO oxidation to CO(2) at its active site C-cluster.
- Recent structural studies have elucidated the R. rubrum CODH and its active site NiFeS cluster (C-cluster).
Purpose of the Study:
- To investigate the CO(2) reduction to formate as a potential side reaction catalyzed by CODH.
- To determine the role of the active site nickel (Ni) in this formate-producing capability.
Main Methods:
- Enzyme assays were performed on both Ni-containing and Ni-deficient forms of R. rubrum CODH.
- Analysis focused on the detection and quantification of formate production.
Main Results:
- Carbon monoxide dehydrogenase (CODH) catalyzes the reduction of CO(2) to formate.
- This formate production is a slow side reaction.
- The reaction occurs irrespective of the presence or absence of nickel (Ni) in the enzyme's active site.
Conclusions:
- Rhodospirillum rubrum CODH exhibits an uncharacterized capability to reduce CO(2) to formate.
- The active site nickel (Ni) is not essential for this CO(2) reduction side reaction.
- This finding expands the known catalytic repertoire of CODH enzymes.
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