Journal
FEBS JOURNAL
Volume 278, Issue 10, Pages 1769-1778Publisher
WILEY-BLACKWELL
DOI: 10.1111/j.1742-4658.2011.08101.x
Keywords
CtaA; cytochrome c oxidase; heme a synthase; Leigh syndrome; oxidase assembly
Categories
Funding
- DFG [SFB 472, EXC 115]
Ask authors/readers for more resources
Biogenesis of cytochrome c oxidase (COX) is a highly complex process involving > 30 chaperones in eukaryotes; those required for the incorporation of the copper and heme cofactors are also conserved in bacteria. Surf1, associated with heme a insertion and with Leigh syndrome if defective in humans, is present as two homologs in the soil bacterium Paracoccus denitrificans, Surf1c and Surf1q. In an in vitro interaction assay, the heme a transfer from purified heme a synthase, CtaA, to Surf1c was followed, and both Surf proteins were tested for their heme a binding properties. Mutation of four strictly conserved amino acid residues within the transmembrane part of each Surf1 protein confirmed their requirement for heme binding. Interestingly the mutation of a tryptophan residue in transmembrane helix II (W200 in Surf1c and W209 in Surf1q) led to a drastic switch in the heme composition, with Surf1 now being populated mostly by heme o, the intermediate in the heme a biosynthetic pathway. This tryptophan residue discriminates between the two heme moieties, apparently coordinates the formyl group of heme a, and most likely presents the cofactor in a spatial orientation suitable for optimal transfer to its target site within subunit I of cytochrome c oxidase.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available