title: [Molecular effects of mitochondrial mutations in cytochrome b of complex III and their impact on the levels of free radical production].
abstract: Cytochrome bc1(mitochondrial complex III) is a common element of several bioenergetic systems. This enzyme catalyses electron transfer from ubiquinol to cytochrome c coupled to translocation of protons across the membrane, which contributes to generation of protonmotive force utilized for ATP production. Cytochrome b, together with cytochrome c1and iron-sulfur protein (ISP), forms the evolutionarily conserved catalytic core. Transfer of electrons within this enzyme, is facilitated by the movement of ISP domain that allows communication between cytochrome b and cytochrome c1. Mutations in the subunits of catalytic core may cause mitochondrial diseases, however elucidation of their molecular effects in human cells is difficult. For that reason yeast or bacterial systems are used. It was found that some mutations in cytochrome b influence the movement of ISP and, in consequence, the levels of superoxide generation. By exploring the effects of mitochondrial mutations in model systems one can not only learn about molecular basis of diseases but also gain insights about catalytic and side reactions in cytochrome bc1.
authors.affiliation: Department of Molecular Biophysics; Faculty of Biochemistry, Biophysics and Biotechnology; Jagiellonian University; 7 Gronostajowa St., 30-387 Kraków, Poland.
authors.forename: Arkadiusz
authors.initials: A
authors.lastname: Borek
authors.affiliation: Department of Molecular Biophysics; Faculty of Biochemistry, Biophysics and Biotechnology; Jagiellonian University; 7 Gronostajowa St., 30-387 Kraków, Poland.
authors.forename: Robert
authors.initials: R
authors.lastname: Ekiert
authors.affiliation: Department of Molecular Biophysics; Faculty of Biochemistry, Biophysics and Biotechnology; Jagiellonian University; 7 Gronostajowa St., 30-387 Kraków, Poland.
authors.forename: Artur
authors.initials: A
authors.lastname: Osyczka
mesh_terms: D045303:Cytochromes b / Q000235:genetics*; D014450:Electron Transport Complex III; D005609:Free Radicals / Q000378:metabolism*; D006801:Humans; D028361:Mitochondrial Diseases / Q000201:enzymology*; D009154:Mutation; D018384:Oxidative Stress
chemical_list: D005609:Free Radicals; D045303:Cytochromes b; D014450:Electron Transport Complex III
keywords: ROS; cytochrome b; domain movement; mitochondrial complex III; mitochondrial mutations; superoxide radical