Structural analysis of atovaquone-inhibited cytochrome bc1 complex reveals the molecular basis of antimalarial drug action.Birth, D., Kao, W.C., Hunte, C.
(2014) Nat Commun 5: 4029-4029
- PubMed: 24893593
- DOI: https://doi.org/10.1038/ncomms5029
- Primary Citation of Related Structures:
- PubMed Abstract:
Atovaquone, a substituted hydroxynaphthoquinone, is a potent antimalarial drug that acts by inhibiting the parasite's mitochondrial cytochrome bc1 complex (cyt bc1). Mutations in cyt bc1 confer atovaquone resistance. Here we describe the X-ray structure of mitochondrial cyt bc1 from Saccharomyces cerevisiae with atovaquone bound in the catalytic Qo site, at 3.0-Å resolution. A polarized H-bond to His181 of the Rieske protein in cyt bc1 traps the ionized hydroxyl group of the drug. Side chains of highly conserved cytochrome b residues establish multiple non-polar interactions with the napththoquinone group, whereas less-conserved residues are in contact with atovaquone's cyclohexyl-chlorophenyl tail. Our structural analysis reveals the molecular basis of atovaquone's broad target spectrum, species-specific efficacies and acquired resistances, and may aid drug development to control the spread of resistant parasites.
Institute for Biochemistry and Molecular Biology, ZMBZ, BIOSS Centre for Biological Signalling Studies, University of Freiburg, Stefan-Meier-Strasse 17, 79104 Freiburg, Germany.