Cytochrome b5 as Electron Donor for Oxy‐cytochrome P‐450
- 1 June 1981
- journal article
- research article
- Published by Wiley in European Journal of Biochemistry
- Vol. 116 (3) , 521-526
- https://doi.org/10.1111/j.1432-1033.1981.tb05367.x
Abstract
The steady-state concentration of the oxycomplex of rat liver microsomal cytochrome P-450 in the presence of NADPH could be elevated by increasing pH and ionic strength or by adding anti-(cytochrome b5) immunoglobulin. Low pH, low ionic strength and incorporation of cytochrome b5 into microsomal membranes decreased the steadystate level. Parallel to these effects, the b5 antibody inhibited monooxygenase activity at low pH and low ionic strength, but was not effective at high pH and high ionic strength. This establishes a role for cytochrome b5 in donating electrons for the reduction of oxy-cytochrome P-450 to the active oxygen complex of cytochrome P-450 but also points to large variations in the importance of this role depending on the experimental conditions, the species of P-450 involved and the substrates employed.This publication has 20 references indexed in Scilit:
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