Download MendeleyMIA40 is an oxidoreductase that catalyzes oxidative protein folding in mitochondria.
Banci, L., Bertini, I., Cefaro, C., Ciofi-Baffoni, S., Gallo, A., Martinelli, M., Sideris, D.P., Katrakili, N., Tokatlidis, K.(2009) Nat Struct Mol Biol 16: 198-206
- PubMed: 19182799
- DOI: https://doi.org/10.1038/nsmb.1553
- Primary Citation of Related Structures:
2K3J - PubMed Abstract:
MIA40 has a key role in oxidative protein folding in the mitochondrial intermembrane space. We present the solution structure of human MIA40 and its mechanism as a catalyst of oxidative folding. MIA40 has a 66-residue folded domain made of an alpha-helical hairpin core stabilized by two structural disulfides and a rigid N-terminal lid, with a characteristic CPC motif that can donate its disulfide bond to substrates. The CPC active site is solvent-accessible and sits adjacent to a hydrophobic cleft. Its second cysteine (Cys55) is essential in vivo and is crucial for mixed disulfide formation with the substrate. The hydrophobic cleft functions as a substrate binding domain, and mutations of this domain are lethal in vivo and abrogate binding in vitro. MIA40 represents a thioredoxin-unrelated, minimal oxidoreductase, with a facile CPC redox active site that ensures its catalytic function in oxidative folding in mitochondria.
Organizational Affiliation:
Magnetic Resonance Center CERM, University of Florence, Via Luigi Sacconi 6, 50019, Sesto Fiorentino, Florence, Italy.
