glutathione

glutathione /glu·ta·thi·one/ (gloo″tah-thi´ōn) a tripeptide of glutamic acid, cysteine, and glycine, existing in reduced (GSH) and oxidized (GSSG) forms and functioning in various redox reactions: in the destruction of peroxides and free radicals, as a cofactor for enzymes, and in the detoxification of harmful compounds. It is also involved in the formation and maintenance of disulfide bonds in proteins and in transport of amino acids across cell membranes.

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glu·ta·thi·one (glt-thn)

n.

A tripeptide of the amino acids glycine, cystine, and glutamic acid occurring widely in plant and animal tissues and forming reduced and oxidized forms important in biological oxidation-reduction reactions.

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Glutathione

A molecule that acts as a co-enzyme in cellular oxidation-reduction reactions.

Mentioned in: Glucose-6-Phosphate Dehydrogenase Deficiency

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glutathione

[glo̅o̅′təthī′ōn]

Etymology: L, gluten + Gk, theione, sulfur

a tripeptide of glutamic acid, cysteine, and glycine whose deficiency is commonly associated with hemolytic anemia. It functions by taking up and giving off hydrogen. It transports amino acids across cell membranes and conjugates to drugs enabling excretion.

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glutathione (glōō·t·thīˑ·ōn),

n a tripeptide that comprises cysteine, glutamic acid, and glycine. An important antioxidant, instrumental in the glutathione conjugation detoxifica-tion pathway. See also glutathione conjugation.

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glutathione (gloo´tthī´ōn),

n an enzyme whose deficiency is commonly associated with hemolytic anemia.

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glutathione

reduced glutathione (GSH), a tripeptide containing glutamic acid, cysteine and glycine, which serves as a reducing agent in many biochemical reactions, being converted to oxidized glutathione (GSSG) in which the cysteine residues of two glutathione molecules are connected by a disulfide bridge. Reduced glutathione is important in protecting erythrocytes from oxidation and hemolysis; deficiency causes sensitivity to oxidant drugs.

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glutathione peroxidase

a selenium-containing enzyme whose blood level is a good indicator of the selenium status of the animal; occurs in a plasma form, an enzyme with specificity for phospholipids, and an intracellular form. Called also GPx.

glutathione reductase

a flavin enzyme involved in the defense of the erythrocyte against hemolysis. A partial deficiency occurs relatively frequently but is due to a deficiency of riboflavin; called also GR.

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glutathione

γ-Glutamyl-cysteinyl-glycine A ubiquitous antioxidant tripeptide involved in CNS metabolism, which serves as a coenzyme for some enzymes of oxidation-reduction systems, transmembrane amino acid transport, maintaining RBC integrity, and prevention of H₂O₂ accumulation in RBCs. See Antioxidant, Antioxidant therapy, Free radical, Free radical scavenger.