Complex cytochrome bcl

Atovaquone, a hydroxynaphthoquinone, selectively inhibits the respiratory chain of protozoan mitochondria at the cytochrome bcl complex (complex III) by mimicking the natural substrate, ubiquinone. Inhibition of cytochrome bcl disrupts the mitochondrial electron transfer chain and leads to a breakdown of the mitochondrial membrane potential. Atovaquone is effective against all parasite stages in humans, including the liver stages. 

Mechanism of Action A systemic anti-infective that inhibits the mitochondrial electron-transport system at the cytochrome bcl complex (Complex 111), which interrupts nucleic acid and adenosine triphosphate synthesis. Therapeutic Effect Antiprotozoal and antipneumocystic activity. 

Nomura H, Athauda SB, Wada H, Maruyama Y, Takahashi K, Inoue H (2006) Identification and reverse genetic analysis of mitochondrial processing peptidase and the core protein of the cytochrome bcl complex of Caenorhabditis elegans, a model parasitic nematode. J Biochem (Tokyo) 139 967-979... 

Rajagukguk S, Yang S, Yu C-A, Yu L, Durham B, Millett F. Effect of mutations in the cytochrome b of loop on the electron-transfer reactions of the Rieske iron-sulfur protein in the cytochrome bcl complex. Biochemistry 2007 46 1791-8. 

Akiba, T., Toyoshima, C., Matsunaga, T., Kawamoto, M., Kubota, T., Fukuyama, K., Namba, K., and Matsubara, H., 1996, Three-dimensional structure of bovine cytochrome bcl complex by electron cryomicroscopy and helical image reconstruction. Nature Struct. Biol. 3 553n561. 

Brandt, U., 1998, The chemistry and mechanics of ubihydroquinone oxidation at center P (Qo) of the cytochrome bcl complex, Biochim. Biophys. Acta 1365 261n208. 

Brandt, U., Yu, L., Yu, C. A., and Trumpower, B. L., 1993, The mitochondrial targeting presequence of the Rieske iron-sulfur protein is processed in a single step after insertion into the cytochrome bcl complex in mammals and retained as a subunit in the complex, J. Biol. Chem. 268 8387n8390. 

Braun, H. P., Emmermann, M., Kruft, V., Bodicker, M., and Schmitz, U. K., 1995, The general mitochondrial processing peptidase from wheat is integrated into the cytochrome bcl-complex of the respiratory chain, Planta 195 396n402. 

Britt, R. D., Sauer, K., Klein, M. P., Knaff, D. B., Kriauciunas, A., Yu, C. A., Yu, L., and Malkin, R., 1991, Electron spin echo envelope modulation spectroscopy supports the suggested coordination of two histidine ligands to the Rieske Fe-S centers of the cytochrome b6f complex of spinach and the cytochrome bcl complexes of Rhodospirillum rubrum, Rhodobacter sphaeroides, and bovine heart mitochondria. Biochemistry 30 1892nl901. 

Ding, H., Robertson, D. E., Daldal, F., and Dutton, P. L., 1992, Cytochrome bcl complex [2Fe-2S] cluster and its interaction with ubiquinone and ubihydroquinone at the Qo site a double-occupancy Qo site model, Biochemistry 31 3144n3158. 

Iwata, S., Saynovits, M., Link, T. A., and Michel, H., 1996, Structure of a water soluble fragment of the iRieskei iron-sulfur protein of the bovine heart mitochondrial cytochrome bcl complex determined by MAD phasing at 1.5 resolution. Structure 4 567n579. 

Schroter, T., Hatzfeld, O. M., Gemeinhardt, S., Kom, M., Friedrich, T., Ludwig, B., and Link, T. A., 1998, Mutational analysis of residues forming hydrogen bonds in the Rieske [2Fe-2S] cluster of the cytochrome bcl complex in Paracoccus denitrificans, Eur. J. Biochem. 255 100nl06. 

Van Doren, S. R., Yun, C.-H., Crofts, A. R., and Gennis, R., 1993, Assembly of the Rieske iron-sulfur subunit of the cytochrome bcl complex in Escherichia coli and Rhodobacter sphaeroides membranes independent of the cytochrome b and cl subunits. Biochemistry 32 628n636. 

Hunte, C., Koepke, J., Eange, C., Rossmanith, T., Michel, H. (2000). Structure at 2.3 A resolution of the cytochrome bcl complex from the yeast Saccharomyces cerevisiae with an antibody EV fragment. Structure, 8, 669—684. 

Hunte, C. (2001). Insights from the structure of the yeast cytochrome bcl complex crystallization of membrane proteins with antibody fragments. FEBS Letters, 504, 126—132. 

Lange, C., Nett, J.H., Trumpower, B.L. and Hunte, C., Specific roles of protein-phospholipid interactions in the yeast cytochrome bcl complex structure, Embo J 20 (2001) 6591-6600. 

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