Ma. Simonyan et al., CYTOCHROMES B-558 FROM BLOOD-SERUM AND ERYTHROCYTE-MEMBRANES, ISOLATION, PURIFICATION, AND PARTIAL CHARACTERIZATION, Biochemistry, 60(12), 1995, pp. 1509-1516
Four types of water-soluble cytochromes b-558 were isolated and purifi
ed for the first time from human placental and rat blood serum and ery
throcyte membranes. They are: b-558 (I) and b-558 (II) from blood seru
m and b-558 (III) and b-558 (IV) from erythrocyte membranes. The isola
ted cytochromes differ in their acid-base properties, molecular weight
s (110, 95, 125, and 80 kD for b-558(I-IV), respectively), composition
(b-558 (III) and b-558 (IV) are lipoproteins), and absorption maxima
in the wavelength range 340-360 nm. The cytochromes have nearly identi
cal absorption maxima in the wavelength range 600-400 nm (560, 530, an
d 412 nm in the oxidized state and 558, 525, and 420 nm in the reduced
state), thus resembling cytochromes b-558 isolated from membranes of
blood formed elements.