Functional Aspects of Protein-Protein Interactions of Cytochrome P450 Cytochrome b5 and Cytochrome P450 Reductase

  • John B. Schenkman
Part of the NATO ASI Series Advanced Science Institutes Series book series (NSSA, volume 202)


While cytochrome P450 has only been known for a relatively short time (1), and its role in xenobiotic metabolism has been known for an even shorter period (2), cytochrome b5 has been known for a much longer time (see review, 3). Both of these hemoproteins are present in the endoplasmic reticulum of a number of tissue, particularly the liver. Only in the last two decades has cytochrome b5 been found to play a role in liver microsomal monooxygenations (4–6). The original report of cytochrome b5 involvement in P450 monooxygenations (7) was an attempt to explain NADH synergism of NADPH-supported drug oxidations (8). Subsequent studies including those discussed in this lecture, have resulted in implication of cytochrome b5 in P450 monooxygenations, but do not explain the earlier reported NADH-synergism.


P450 Reductase Cytochrome P450 Reductase Redox Partner Charge Pairing Spin Equilibrium 
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Copyright information

© Plenum Press, New York 1991

Authors and Affiliations

  • John B. Schenkman
    • 1
  1. 1.Department of PharmacologyUniversity of Connecticut Health CenterFarmingtonUSA

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