flavin

flavin /fla·vin/ (fla´vin) any of a group of water-soluble yellow pigments widely distributed in animals and plants, including riboflavin and yellow enzymes.

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flavin adenine dinucleotide  (FAD) a coenzyme composed of riboflavin 5'-phosphate (FMN) and adenosine 5'-phosphate in pyrophosphate linkage; it forms the prosthetic group of certain enzymes, including d-amino acid oxidase and xanthine oxidase, serving as an electron carrier by being alternately oxidized (FAD) and reduced (FADH2). It is important in electron transport in mitochondria.

flavin mononucleotide  (FMN) riboflavin 5'-phosphate; it acts as a coenzyme for a number of oxidative enzymes, including NADH dehydrogenase, serving as an electron carrier by being alternately oxidized (FMN) and reduced (FMNH2).

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fla·vin (flvn) or fla·vine (-vn)

n.

1. Any of various water-soluble yellow pigments, including riboflavin, found in plant and animal tissue as coenzymes of flavoproteins.

2. A ketone that gives color to various natural yellow pigments.

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flavin

any of a group of water-soluble yellow pigments widely distributed in animals and plants, including riboflavin and yellow enzymes.

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flavin adenine dinucleotide (FAD)

a coenzyme that is a condensation product of riboflavin phosphate and adenylic acid; it forms the prosthetic group of certain enzymes, including d-amino acid oxidase and xanthine oxidase, and is important in electron transport in mitochondria.

flavin-linked dehydrogenases

class of dehydrogenases with prosthetic groups containing either flavin mononucleotide or flavin adenine dinucleotide tightly bound to the enzyme structure. Example is succinate dehydrogenase of the TCA cycle.

flavin mononucleotide (FMN)

a derivative of riboflavin consisting of a three-ring system (isoalloxazine) attached to an alcohol (ribitol); it acts as a coenzyme for a number of oxidative enzymes, including l-amino acid oxidase and cytochrome C reductase.