PMID: 15341729 , Related PDB id: 1S3A

Authors:

Brockmann C, Diehl A, Rehbein K, Strauss H, Schmieder P, Korn B, Kuhne R, Oschkinat H

Title:

The oxidized subunit B8 from human complex I adopts a thioredoxin fold.

Journal:

Structure. 2004 Sep;12(9):1645-54.

Abstract:

Subunit B8 from ubiquinone oxidoreductase (complex I) (CI-B8) is one of several nuclear-encoded supernumerary subunits that are not present in bacterial complex I. Its solution structure shows a thioredoxin fold with highest similarities to the human thioredoxin mutant C73S and thioredoxin 2 from Anabeana sp. Interestingly, these proteins contain active sites in the same area, where the disulfide bond of oxidized CI-B8 is located. The redox potential of this disulfide bond is -251.6 mV, comparing well to that of disulfides in other thioredoxin-like proteins. Analysis of the structure reveals a surface area that is exclusively composed of highly conserved residues and thus most likely a subunit interaction site within complex I.