The Flavin-Containing Monooxygenase (EC

  • Ernest Hodgson
  • Patricia E. Levi
Part of the NATO ASI Series Advanced Science Institutes Series book series (NSSA, volume 202)


The flavin-containing monooxygenase (EC (FMO), originally described as an amine oxidase, was subsequently shown to be a versatile sulfur oxidase, the early studies being summarized by Ziegler (1). The FMO has been shown more recently to be a phosphorus oxidase (2,3). This enzyme and the cytochrome P450-dependent monooxygenase system are the two principal enzymes that catalyze the oxidation of lipophilic xenobiotics to electrophilic products capable of further metabolism, either to readily excretable conjugation products or to reactive intermediates with potential for adverse effects. Much of what is known about the substrate specificity of the FMO, is summarized in a recent review (4). Purification of pig liver FMO was accomplished some time ago (5) and the ability of the solubilized enzyme to catalyze the oxidation of the same wide variety of nucleophilic nitrogen, sulfur and phosphorus compounds as the membrane-bound enzyme has been established (1-5). The physiological role for this enzyme is not well known but may be involved in the maintenance of cellular thiol:disulfide ratios by the oxidation of cysteamine to cystamine (6).


Rabbit Lung Primary Aliphatic Amine Piperonyl Butoxide Microsomal Oxidation Nucleophilic Nitrogen 
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Copyright information

© Plenum Press, New York 1991

Authors and Affiliations

  • Ernest Hodgson
    • 1
  • Patricia E. Levi
    • 1
  1. 1.Department of ToxicologyNorth Carolina State UniversityRaleighUSA

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