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Flavin-Containing Monooxygenases: Substrate Specificity and Complex Metabolic Pathways

  • Ernest Hodgson
  • Bonnie L. Blake
  • Patricia E. Levi
  • Richard B. Mailman
  • Michael P. Lawton
  • Richard M. Philpot
  • Mary Beth Genter
Part of the NATO ASI Series book series (volume 90)

Abstract

The flavin-containing monooxygenase (EC 1.14.13.8)(FMO) is located in the endoplasmic reticulum of mammalian cells and is involved in the monooxygenation of a wide variety of xenobiotics. The FMO has a similar distribution and function to many of the isozymes of cytochrome P450 (P450). Originally described as an amine oxidase (Ziegler and Mitchell, 1972), it is now known to catalyze the oxidation of many organic, and some inorganic, chemicals (Ziegler, 1990, 1991). The FAD prosthetic group first reacts with NADPH and then molecular oxygen to give rise to the enzyme-bound hydroperoxyflavin responsible for the oxidation of suitable substrates. These initial reactions occur in the absence of substrate and the enzyme exists primarily in the hydroperoxyflavin form (Poulsen and Ziegler, 1979, Beaty and Ballou, 1981a,b). A consequence of this is that substrates, with few exceptions, have the same Vmax, although Km may vary.

Keywords

Boronic Acid Amine Oxidase Piperonyl Butoxide Microsomal Oxidation Complex Metabolic Pathway 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • Ernest Hodgson
    • 1
  • Bonnie L. Blake
    • 1
  • Patricia E. Levi
    • 1
  • Richard B. Mailman
    • 1
    • 2
  • Michael P. Lawton
    • 1
    • 3
  • Richard M. Philpot
    • 1
    • 3
  • Mary Beth Genter
    • 1
  1. 1.Department of ToxicologyNorth Carolina State UniversityRaleighUSA
  2. 2.Brain & Development Research CenterUniversity of North Carolina School of MedicineChapel HillUSA
  3. 3.National Institute of Environmental Health SciencesUSA

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