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Updated: Jun 3, 2026
06:01
EPR Monitored Redox Titration of the Cofactors of Saccharomyces cerevisiae Nar1
Published on: November 26, 2014
Biosynthesis of complex iron-sulfur enzymes.
Eric M Shepard1, Eric S Boyd, Joan B Broderick
1The Astrobiology Biogeocatalysis Research Center and the Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, United States.
Current Opinion in Chemical Biology
|March 12, 2011
Summary
Complex iron-sulfur (Fe-S) cluster biosynthesis for [FeFe]-hydrogenases and nitrogenases shares common pathways. Radical S-adenosylmethionine (SAM) enzymes modify Fe-S precursors on scaffold proteins, enabling cluster transfer for enzyme maturation.
Area of Science:
- Biochemistry
- Enzymology
- Bioinorganic Chemistry
Background:
- Complex iron-sulfur (Fe-S) clusters are essential prosthetic groups in enzymes like [FeFe]-hydrogenases and nitrogenases.
- Understanding the biosynthesis of these intricate clusters is crucial for elucidating enzyme function.
Purpose of the Study:
- To explore the parallels in the biosynthesis pathways of the H-cluster ([FeFe]-hydrogenase) and FeMo-co (nitrogenase).
- To identify common mechanisms underlying the maturation of these metalloenzymes.
Main Methods:
- Analysis of Fe-S cluster precursor synthesis by host cell machinery (Isc/Suf).
- Investigation of modifications introduced by radical S-adenosylmethionine (SAM) enzymes on scaffold proteins.
- Study of the transfer of modified Fe-S clusters to apo-proteins.
Main Results:
- Identified conserved steps involving Fe-S cluster precursor modification by radical SAM enzymes.
- Demonstrated the role of unique scaffold proteins in these modifications.
- Showcased the final transfer of mature clusters to apo-proteins for enzyme assembly.
Conclusions:
- The biosynthesis of complex Fe-S clusters for [FeFe]-hydrogenases and nitrogenases follows unifying paradigms.
- Radical SAM enzymes and scaffold proteins play critical roles in modifying and transferring Fe-S clusters.
- These findings provide a framework for understanding the assembly of metalloenzymes with complex Fe-S cofactors.
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