Crystallization and preliminary X-ray crystallographic studies of bovine heart mitochondrial cytochrome bc1 complex.
Cytochrome bc1 complex (ubiquinol:ferricytochrome c oxidoreductase, EC. 1.10.2.2) from bovine heart mitochondria was crystallized by a batchwise method from protein solution containing sucrose monolaurate using polyethylene glycol-4000 as a precipitant. The red parallelepiped crystals grew to a size of approximately 1 mm x 1 mm x 1 mm. The crystalline protein showed enzymic activity catalyzing electron transfer from ubiquinol-2 to cytochrome c. The subunit composition and absorption spectrum of the crystalline enzyme were identical to those reported previously for the enzyme in solution. The crystal diffracted X-rays to 7.5 A resolution. The diffraction pattern indicated a monoclinic form, space group P2(1), and unit-cell constants of a = 196 A, b = 179 A, c = 253 A and beta = 97 degrees. Most probably four functional units are present in an asymmetric unit.
Kubota
T
T
Department of Biology, Faculty of Science, Osaka University, Japan.
Kawamoto
M
M
Fukuyama
K
K
Shinzawa-Itoh
K
K
Yoshikawa
S
S
Matsubara
H
H
D000818:Animals; D002417:Cattle; D014450:Electron Transport Complex III / Q000737:chemistry*; D004591:Electrophoresis, Polyacrylamide Gel; D008929:Mitochondria, Heart / Q000201:enzymology*; D014961:X-Ray Diffraction
D014450:Electron Transport Complex III