Enzyme Structure
ETF-QO consists of one structural domain with three functional domains packed in close proximity: a FAD domain, a 4Fe4S cluster domain, and a UQ-binding domain.
FAD is in an extended conformation and is buried deeply within its functional domain. Multiple hydrogen bonds and a positive helix dipole modulate the redox potential of FAD and can possibly stabilize the anionic semiquinone intermediate. The 4Fe4S cluster is also stabilized by extensive hydrogen bonding around the cluster and its cysteine components. Ubiquinone binding is achieved through a deep hydrophobic binding pocket which is a different mode than other UQ-binding proteins such as succinate-Q oxidoreductase. Although ETF-QO is an integral membrane protein, it does not traverse the entire membrane unlike other UQ-binding proteins.
Read more about this topic: Electron-transferring-flavoprotein Dehydrogenase
Famous quotes containing the word structure:
“Women over fifty already form one of the largest groups in the population structure of the western world. As long as they like themselves, they will not be an oppressed minority. In order to like themselves they must reject trivialization by others of who and what they are. A grown woman should not have to masquerade as a girl in order to remain in the land of the living.”
—Germaine Greer (b. 1939)