Flavoproteins – L and D amino acids

  Flavoproteins are the proteins that include a nucleic acid derivative of riboflavin, namely the Flavin Adenine Dinucleotide (FAD) or Flavin Mononucleotide (FMN).

The flavoproteins come under the roof of enzyme families, any of the class of conjugated proteins that contain flavins and are involved in oxidation reactions in cells.

L amino acid and D amino acid are these oxidases forms of them, namely L- amino acid oxidase & D-amino acid oxidase.

Removal of two hydrogen atoms by the flavin coenzyme results in the formation of an unstable α-amino acid intermediate, where this intermediate undergoes decomposition by addition of water and forms the ammonium ion and the corresponding α-keto acid: L-amino acid oxidase occurs in the liver and kidney only.

This is the flavoprotein that contains flavin mononucleotide (FMN) as a prosthetic group. Similarly, high levels of D-amino acid oxidase are found again in the liver and kidney. This enzyme contains flavin adenine dinucleotide (FAD) and deaminates many D amino acids and glycine.

Flavoproteins are involved in a wide variety of biological processes, including the removal of radicals contributing to oxidative stress, photosynthesis, and DNA repair.