Document Type
Article
Publication Date
8-15-2012
Abstract
Ferritin-like molecules are unique to cellular iron homeostasis because they can store iron at concentrations much higher than those dictated by the solubility of Fe3+. Very little is known about the protein interactions that deliver iron for storage or promote the mobilization of stored iron from ferritin-like molecules. Here, we report the X-ray crystal structure of Pseudomonas aeruginosa bacterioferritin (Pa-BfrB) in complex with bacterioferritin-associated ferredoxin (Pa-Bfd) at 2.0 Å resolution. As the first example of a ferritin-like molecule in complex with a cognate partner, the structure provides unprecedented insight into the complementary interface that enables the [2Fe-2S] cluster of Pa-Bfd to promote heme-mediated electron transfer through the BfrB protein dielectric (∼18 Å), a process that is necessary to reduce the core ferric mineral and facilitate mobilization of Fe2+. The Pa-BfrB-Bfd complex also revealed the first structure of a Bfd, thus providing a first view to what appears to be a versatile metal binding domain ubiquitous to the large Fer2-BFD family of proteins and enzymes with diverse functions. Residues at the Pa-BfrB-Bfd interface are highly conserved in Bfr and Bfd sequences from a number of pathogenic bacteria, suggesting that the specific recognition between Pa-BfrB and Pa-Bfd is of widespread significance to the understanding of bacterial iron homeostasis. © 2012 American Chemical Society.
Publication Source (Journal or Book title)
Journal of the American Chemical Society
First Page
13470
Last Page
13481
Recommended Citation
Yao, H., Wang, Y., Lovell, S., Kumar, R., Ruvinsky, A., Battaile, K., Vakser, I., & Rivera, M. (2012). The structure of the BfrB-Bfd complex reveals protein-protein interactions enabling iron release from bacterioferritin. Journal of the American Chemical Society, 134 (32), 13470-13481. https://doi.org/10.1021/ja305180n
