4u3g
Crystal structure of Escherichia coli bacterioferritin mutant D132FCrystal structure of Escherichia coli bacterioferritin mutant D132F
Structural highlights
FunctionBFR_ECOL6 Iron-storage protein, whose ferroxidase center binds Fe(2+) ions, oxidizes them by dioxygen to Fe(3+), and participates in the subsequent Fe(3+) oxide mineral core formation within the central cavity of the protein complex (By similarity). Publication Abstract from PubMedBacterioferritin is a bacterial iron storage and detoxification protein that is capable of forming a ferric oxyhydroxide mineral core within its central cavity. To do this, iron must traverse the bacterioferritin protein shell, which is expected to occur through one or more of the channels through the shell identified by structural studies. The size and negative electrostatic potential of the 24 B-type channels suggest that they could provide a route for iron into bacterioferritin. Residues at the B-type channel (N34, E66, D132, and D139)of E. coli bacterioferritin were substituted to determine if they are important for iron core formation. A significant decrease in the rates of initial oxidation of Fe(II) at the ferroxidase center and subsequent iron mineralization was observed for the D132F variant. The crystal structure of this variant shows that substitution of residue 132 with phenylalanine caused a steric blockage of the B-type channel and no other material structural perturbation. We conclude that the B-type channel is a major route for iron entry into both the ferroxidase center and the iron storage cavity of bacterioferritin. The B-type Channel is a Major Route for Iron Entry into the Ferroxidase Center and Central Cavity of Bacterioferritin.,Wong SG, Grigg JC, Le Brun NE, Moore GR, Murphy ME, Mauk AG J Biol Chem. 2014 Dec 15. pii: jbc.M114.623082. PMID:25512375[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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