Exposing the complex III Qo semiquinone radical.
Complex III Qo site semiquinone has been assigned pivotal roles in productive energy-conversion and destructive superoxide generation. After a 30-year search, a genetic heme bH knockout arrests this transient semiquinone EPR radical, revealing the natural engineering balance pitting energy-conserving, short-circuit minimizing, split electron transfer and catalytic speed against damaging oxygen reduction.
Zhang
Haibo
H
Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA 19104, USA.
Osyczka
Artur
A
Dutton
P Leslie
PL
Moser
Christopher C
CC
D016227:Benzoquinones / Q000737:chemistry*; D003573:Cytochrome b Group / Q000737:chemistry / Q000235:genetics; D014450:Electron Transport Complex III / Q000737:chemistry*; D008928:Mitochondria / Q000201:enzymology*; D010084:Oxidation-Reduction; D016354:Rhodobacter capsulatus / Q000201:enzymology / Q000235:genetics
D016227:Benzoquinones; D003573:Cytochrome b Group; C025232:semiquinone radicals; D014450:Electron Transport Complex III