Crystallographic investigation of the ubiquinone binding site of respiratory Complex II and its inhibitors.Huang, L.S., Lummen, P., Berry, E.A.
(2021) Biochim Biophys Acta Proteins Proteom 1869: 140679-140679
- PubMed: 34089891
- DOI: https://doi.org/10.1016/j.bbapap.2021.140679
- Primary Citation of Related Structures:
6MYO, 6MYP, 6MYQ, 6MYR, 6MYS, 6MYT, 6MYU
- PubMed Abstract:
- 3-nitropropionic acid is a suicide inhibitor of mitochondrial respiration that, upon oxidation by complex II, forms a covalent adduct with a catalytic base arginine in the active site of the enzyme.
Huang, L.S., Sun, G., Cobessi, D., Wang, A.C., Shen, J.T., Tung, E.Y., Anderson, V.E., Berry, E.A.
(2006) J Biol Chem 281: 5965
- Crystallographic studies of the binding of ligands to the dicarboxylate site of Complex II, and the identity of the ligand in the "oxaloacetate-inhibited" state.
Huang, L.S., Shen, J.T., Wang, A.C., Berry, E.A.
(2006) Biochim Biophys Acta 1757: 1073
- Crystallization of mitochondrial respiratory complex II from chicken heart: a membrane-protein complex diffracting to 2.0 A.
Huang, L.S., Borders, T.M., Shen, J.T., Wang, C.J., Berry, E.A.
(2005) Acta Crystallogr D Biol Crystallogr 61: 380
- Crystal structure of mitochondrial respiratory membrane protein complex II.
Sun, F., Huo, X., Zhai, Y., Wang, A., Xu, J., Su, D., Bartlam, M., Rao, Z.
(2005) Cell 121: 1043
The quinone binding site (Q-site) of Mitochondrial Complex II (succinate-ubiquinone oxidoreductase) is the target for a number of inhibitors useful for elucidating the mechanism of the enzyme. Some of these have been developed as fungicides or pesticides, and species-specific Q-site inhibitors may be useful against human pathogens ...
The quinone binding site (Q-site) of Mitochondrial Complex II (succinate-ubiquinone oxidoreductase) is the target for a number of inhibitors useful for elucidating the mechanism of the enzyme. Some of these have been developed as fungicides or pesticides, and species-specific Q-site inhibitors may be useful against human pathogens. We report structures of chicken Complex II with six different Q-site inhibitors bound, at resolutions 2.0-2.4 Å. These structures show the common interactions between the inhibitors and their binding site. In every case a carbonyl or hydroxyl oxygen of the inhibitor is H-bonded to Tyr58 in subunit SdhD and Trp173 in subunit SdhB. Two of the inhibitors H-bond Ser39 in subunit SdhC directly, while two others do so via a water molecule. There is a distinct cavity that accepts the 2-substituent of the carboxylate ring in flutolanil and related inhibitors. A hydrophobic "tail pocket" opens to receive a side-chain of intermediate-length inhibitors. Shorter inhibitors fit entirely within the main binding cleft, while the long hydrophobic side chains of ferulenol and atpenin A5 protrude out of the cleft into the bulk lipid region, as presumably does that of ubiquinone. Comparison of mitochondrial and Escherichia coli Complex II shows a rotation of the membrane-anchor subunits by 7° relative to the iron‑sulfur protein. This rotation alters the geometry of the Q-site and the H-bonding pattern of SdhB:His216 and SdhD:Asp57. This conformational difference, rather than any active-site mutation, may be responsible for the different inhibitor sensitivity of the bacterial enzyme.
Biochemistry and Molecular Biology, SUNY Upstate Medical University, 750 E. Adams Street, Syracuse, N.Y 13210, USA. Electronic address: firstname.lastname@example.org.