carnitine


carnitine
A trimethylammonium (betaine) derivative of γ-amino-β-hydroxybutyric acid, formed from Nε,Nε,Nε-trimethyllysine and from γ-butyrobetaine; the l-isomer is a thyroid inhibitor found in muscle, liver, and meat extracts; l-c. is an acyl carrier with respect to the mitochondrial membrane; it thus stimulates fatty acid oxidation. SYN: BT factor, vitamin BT. [L. caro carn-, flesh + ine]
- c. acetyltransferase an enzyme found in mitochondria that catalyzes the reversible transfer of an acetyl group from acetyl-CoA to c., forming O-acetylcarnitine and coenzyme A. Acetylcarnitine is an important fuel source in sperm.
- c. acylcarnitine translocase a transport protein found in the inner mitochondrial membrane. Transports acylcarnitine derivatives into the mitochondria and transports c. out of the mitochondria. An important step in fatty acid oxidation.
- c. palmitoyltransferase 1. an enzyme that reversibly forms acylcarnitines and coenzyme A from c. and acylcoenzyme A (often, palmitoyl-CoA); important in fatty acid oxidation. Deficiency of isozyme I results in ketogenesis with hypoglycemia; deficiency of isozyme II affects primarily skeletal muscle.

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car·ni·tine 'kär-nə-.tēn n a quaternary ammonium compound C7H15NO3 that is present esp. in vertebrate muscle, is involved in the transfer of fatty acids across mitochondrial membranes, and in humans is obtained from food (as meat or milk) or is synthesized from a lysine derivative

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car·ni·tine (kahrґnĭ-tēn) a betaine derivative found in skeletal muscle and liver; it is required for mitochondrial beta oxidation of fatty acids, carrying the acyl groups (fatty acids) across the mitochondrial membrane to the matrix, where they are transferred back to coenzyme A prior to oxidation. It has been used as an investigational antithyroid and antiangina agent. Deficiency of carnitine leads to buildup of fatty acids in the body.

Medical dictionary. 2011.

Look at other dictionaries:

  • Carnitine — Systematic (IUPAC) name 3 hydroxy 4 (trimethylazaniumyl)butanoate Clinical data AHFS/Drugs.com …   Wikipedia

  • Carnitine — Structure de la carnitine Général Nom IUPAC 3 hydroxy 4 triméthylammonio butanoate …   Wikipédia en Français

  • carnitine — ● carnitine nom féminin Acide aminé dont le déficit peut provoquer une myopathie (maladie grave des muscles). carnitine [kaʀnitin] n. f. ÉTYM. Mil. XXe; du lat. caro, carnis « chair », t de liaison, et suff. ine. ❖ ♦ Chim., biol. Substance… …   Encyclopédie Universelle

  • carnitine — (= b hydroxy b trimethyl aminobutyric acid) Compound that transports long chain fatty acids across the inner mitochondrial membrane in the form of acyl carnitine. Sometimes referred to as Vitamin Bt or Vitamin B7 …   Dictionary of molecular biology

  • carnitine — /kahr ni teen /, n. Biochem. a dipolar compound that occurs in muscle and liver and is involved in the transport of fatty acids across the inner mitochondrial membrane. [1920 25; < G Carnitin, equiv. to L carni (comb. form of caro, gen. carnis… …   Universalium

  • carnitine — karnitinas statusas T sritis chemija formulė Formulę žr. priede. priedas( ai) Grafinis formatas atitikmenys: angl. carnitine; vitamin B rus. витамин B; карнитин ryšiai: sinonimas – (R) 3 hidroksi 4 trimetilamoniobutanoatas sinonimas – vitaminas …   Chemijos terminų aiškinamasis žodynas

  • carnitine — A substance made in the muscles and liver, and also found in certain foods such as meat, poultry, fish, and some dairy products. The body needs carnitine to make energy from fat …   English dictionary of cancer terms

  • carnitine — noun Etymology: International Scientific Vocabulary, from Latin carn , caro Date: circa 1922 a quaternary ammonium compound C7H15NO3 that is present especially in vertebrate muscle and that in the levorotatory form is involved in the transfer of… …   New Collegiate Dictionary

  • carnitine — noun A betaine 3 hydroxy 4 trimethylammonio butanoate that occurs in the liver and has a function in fatty acid transport …   Wiktionary

  • carnitine — car·ni·tine …   English syllables