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Essential Metal Uptake in Gram-negative Bacteria: X-ray Fluorescence, Radioisotopes, and Cell Fractionation
Published on: February 1, 2018
Bacterial ApbC can bind and effectively transfer iron-sulfur clusters
Jeffrey M Boyd1, Antonio J Pierik, Daili J A Netz
1Department of Bacteriology, University of Wisconsin, Madison, Wisconsin 53706, USA.
Biochemistry
|July 12, 2008
Summary
Salmonella enterica ApbC protein, an ATPase, was found to coordinate and transfer iron-sulfur ([Fe-S]) clusters. This discovery reveals ApbC
Area of Science:
- Microbiology
- Biochemistry
- Molecular Biology
Background:
- Iron-sulfur ([Fe-S]) cluster metabolism is crucial but incompletely understood.
- Mutants of Salmonella enterica lacking ApbC exhibit [Fe-S] cluster metabolism defects.
Purpose of the Study:
- To biochemically characterize the function of ApbC in [Fe-S] cluster metabolism.
- To investigate the role of ApbC in [Fe-S] cluster transfer.
Main Methods:
- Purification and biochemical analysis of ApbC.
- Reconstitution of [Fe-S] clusters onto ApbC.
- In vitro activation of Saccharomyces cerevisiae apo-isopropylmalate isomerase (Leu1) by holo-ApbC.
Main Results:
- Purified ApbC is a homodimeric ATPase that can coordinate an [Fe-S] cluster.
- Reconstituted ApbC binds 2 mol of Fe and 2 mol of S per monomer, forming a [4Fe-4S] cluster.
- Holo-ApbC efficiently activates apo-Leu1 in vitro, demonstrating [Fe-S] cluster transfer capability.
Conclusions:
- ApbC acts as an [Fe-S] cluster scaffold protein, coordinating a [4Fe-4S] cluster across its dimer interface.
- ApbC can transfer its coordinated [Fe-S] cluster to an apoprotein.
- This function of ApbC is analogous to eukaryotic homologues, providing insights into conserved [Fe-S] cluster metabolism.
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