phenylalanine


phenylalanine
2-Amino-3-phenylpropionic acid; the l-isomer is one of the common amino acid s in proteins; a nutritionally essential amino acid.
- p. ammonia-lyase a nonmammalian enzyme that catalyzes the conversion of l-p. to trans-cinnamate and ammonia; it has been used in the treatment of phenylketonuria.
- p. 4-hydroxylase SYN: p. 4-monooxygenase.
- p. 4-monooxygenase an enzyme that catalyzes the oxidation of l-p. to l-tyrosine with O2 and tetrahydrobiopterin (the latter forming the dihydro derivative) which is, in turn, reduced by NADPH and a reductase to the active form; a deficiency of either of these enzymes will result in phenylketonuria. SYN: p. 4-hydroxylase.

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phe·nyl·al·a·nine .fen-əl-'al-ə-.nēn, .fēn- n an essential amino acid C9H11NO2 that is obtained in its levorotatory L-form by the hydrolysis of proteins (as lactalbumin), that is essential in human nutrition, and that is converted in the normal body to tyrosine abbr. Phe see PHENYLKETONURIA, PHENYLPYRUVIC ACID

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n.
an essential amino acid that is readily converted to tyrosine. Blockade of this metabolic pathway gives rise to phenylketonuria, which is associated with abnormally large amounts of phenylalanine and phenylpyruvic acid in the blood and retarded mental development.

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phen·yl·al·a·nine (Phe) (F) (fen″əl-alґə-nēn) an aromatic essential amino acid, α-amino-β-phenylpropionic acid; most of that ingested is hydroxylated to form tyrosine, which is used for protein synthesis, but small amounts are transaminated to phenylpyruvic acid or decarboxylated. See also table at amino acid. [USP] a preparation of phenylalanine used as a dietary supplement.

Medical dictionary. 2011.

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  • phénylalanine — [ fenilalanin ] n. f. • 1897; de phényl et alanine ♦ Biochim. Composé aromatique, l un des vingt acides aminés constituants des protéines. ● phénylalanine nom féminin Acide aminé essentiel, cyclique, très répandu, obtenu par hydrolyse de… …   Encyclopédie Universelle

  • phenylalanine — phenylalanine. См. фенилаланин [Фен]. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • phenylalanine — [fen΄əl al′ə nēn΄, fē΄nəlal′ə nēn΄] n. an essential amino acid, C6H5CH2CH(NH2)COOH, occurring in proteins: see AMINO ACID …   English World dictionary

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  • phenylalanine — /fen l al euh neen , nin, feen /, n. Biochem. a crystalline, water soluble, essential amino acid, C6H5CH2CH(NH2)COOH, necessary to the nutrition of humans and most animals, obtained chiefly from egg white or skim milk. Abbr.: Phe; Symbol: F Also… …   Universalium

  • phenylalanine — n. an essential amino acid that is readily converted to tyrosine. Blockade of this metabolic pathway gives rise to phenylketonuria, which is associated with abnormally large amounts of phenylalanine and phenylpyruvic acid in the blood and… …   The new mediacal dictionary

  • phenylalanine — fenilalaninas statusas T sritis chemija formulė C₆H₅CH₂CH(NH₂)COOH santrumpa( os) Phe, F atitikmenys: angl. phenylalanine rus. фенилаланин ryšiai: sinonimas – 2 amino 3 fenilpropano rūgštis …   Chemijos terminų aiškinamasis žodynas

  • phenylalanine — noun Etymology: International Scientific Vocabulary Date: circa 1883 an essential amino acid C9H11NO2 that is converted in the normal body to tyrosine …   New Collegiate Dictionary