9nhr

Structural highlights

Function

BFRB_PSEAE The major iron-storage protein, part of the heterooligomeric bacterioferritin (BFR) complex. The ferroxidase center binds Fe(2+), oxidizes it using dioxygen to Fe(3+), and participates in the subsequent Fe(3+) oxide mineral core formation within the central cavity of the BFR protein shell. Can store up to 600 iron atoms per bacterioferritin protein molecule (PubMed:19575528, PubMed:20067302, PubMed:25640193, PubMed:26368531). In iron-sufficient conditions (10 uM Fe(2+)) iron accumulates in BFR until about 12 hours, when it starts to deplete; stored iron is no longer detectable by 24 hours growth, iron is mobilized from the BFR as levels drop in the growth media (PubMed:28318006). Iron release from the BFR requires ferredoxin NADP reductase (FPR) and bacterioferritin-associated ferredoxin (Bfd) (PubMed:19575528, PubMed:22812654, PubMed:26368531). Reduction of the BfrB heme group occurs in the presence of Bfd, strongly suggesting that the BfrB-Bfd complex allows heme to mediate electron transfer from FPR to the Fe(3+) iron core in the BFR shell prior to its release as Fe(2+) (PubMed:19575528, PubMed:22812654, PubMed:26368531).^{[1] [2] [3] [4] [5] [6]}

References

1. ↑ Weeratunga SK, Gee CE, Lovell S, Zeng Y, Woodin CL, Rivera M. Binding of Pseudomonas aeruginosa apobacterioferritin-associated ferredoxin to bacterioferritin B promotes heme mediation of electron delivery and mobilization of core mineral iron. Biochemistry. 2009 Aug 11;48(31):7420-31. PMID:19575528 doi:10.1021/bi900561a
2. ↑ Weeratunga SK, Lovell S, Yao H, Battaile KP, Fischer CJ, Gee CE, Rivera M. Structural Studies of Bacterioferritin B from Pseudomonas aeruginosa Suggest a Gating Mechanism for Iron Uptake via the Ferroxidase Center . Biochemistry. 2010 Jan 21. PMID:20067302 doi:10.1021/bi9015204
3. ↑ Yao H, Wang Y, Lovell SW, Kumar R, Ruvinsky AM, Battaile KP, Vakser IA, Rivera M. The structure of the BfrB-Bfd complex reveals protein-protein interactions enabling iron release from bacterioferritin. J Am Chem Soc. 2012 Jul 19. PMID:22812654 doi:10.1021/ja305180n
4. ↑ Yao H, Rui H, Kumar R, Eshelman K, Lovell S, Battaile KP, Im W, Rivera M. Concerted Motions Networking Pores and Distant Ferroxidase Centers Enable Bacterioferritin Function and Iron Traffic. Biochemistry. 2015 Jan 31. PMID:25640193 doi:http://dx.doi.org/10.1021/bi501255r
5. ↑ Wang Y, Yao H, Cheng Y, Lovell SW, Battaile KP, Middaugh CR, Rivera M. Characterization of the Bacterioferritin/Bacterioferritin Associated Ferredoxin (BfrB:Bfd) Protein-Protein Interaction in Solution and Determination of Binding Energy Hot Spots. Biochemistry. 2015 Sep 28. PMID:26368531 doi:http://dx.doi.org/10.1021/acs.biochem.5b00937
6. ↑ Eshelman K, Yao H, Punchi Hewage AND, Deay JJ, Chandler JR, Rivera M. Inhibiting the BfrB:Bfd interaction in Pseudomonas aeruginosa causes irreversible iron accumulation in bacterioferritin and iron deficiency in the bacterial cytosol. Metallomics. 2017 Jun 21;9(6):646-659. PMID:28318006 doi:10.1039/c7mt00042a