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Flavin Coenzymes

  1. Sandro Ghisla1,
  2. Dale E Edmondson2

Published Online: 15 SEP 2009

DOI: 10.1002/9780470015902.a0000654.pub2



How to Cite

Ghisla, S. and Edmondson, D. E. 2009. Flavin Coenzymes. eLS. .

Author Information

  1. 1

    University of Konstanz, Konstanz, Germany

  2. 2

    Emory University, Atlanta, Georgia, USA

Publication History

  1. Published Online: 15 SEP 2009

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Flavins are yellow chromophores in organisms from bacteria to humans and essential for practically all metabolic processes. They occur in nature in a variety of forms. The core of the flavin cofactor is the (iso)alloxazine nucleus with the most common forms as FMN (flavin mononucleotide) and FAD (flavin-adenine dinucleotide). A number of flavin cofactors are covalently linked to their apoproteins. The covalent linkage is, in general, via a modification of the benzene subnucleus and functional groups of amino acid side chains. As cofactors, flavins are distinguished by their ability to catalyse a variety of different processes involving oxidation-reduction (redox) reactions.

Key Concepts

  • Chemical variation of a basic molecule (the isoalloxazine) leads to several (modified) coenzymes that differ significantly in their catalytic properties.

  • The type and position of the modification is a key determinant for the properties of the (modified) coenzyme.

  • The cofactor interacts with the protein in many different ways. These, in turn, affect the properties of the cofactor as a catalyst. The result is a disparate selection of catalytic functions.


  • FMN;
  • FAD;
  • flavoprotein;
  • alloxazine;
  • cofactor;
  • redox