title: Induction of multiple forms of tyrosine aminotransferase by amino acid mixtures of different compositions.
abstract: Hepatic tyrosine aminotransferase (EC 2.6.1.5) was induced in rats by intubation of amino acid mixtures (complete or tryptophan-free). Enzyme activity was increased 4-fold by the complete mixture and 8-fold by the tryptophan-free mixture. The enzyme was analyzed by chromatography on CM-Sephadex. Chromatographic patterns were characteristic of the type of inducer rather than of the chronology of the induction cycle: after induction by the complete amino acid mixture the three forms of the enzyme were equally increased whereas after induction by the tryptophan-free mixture Form I was preferentially increased.
mesh_terms: D000596:Amino Acids / Q000494:pharmacology*; D000818:Animals; D002852:Chromatography, Ion Exchange; D004790:Enzyme Induction / Q000187:drug effects; D007527:Isoenzymes / Q000096:biosynthesis*; D008099:Liver / Q000187:drug effects / Q000201:enzymology*; D008297:Male; D051381:Rats; D013997:Time Factors; D014364:Tryptophan / Q000494:pharmacology; D014444:Tyrosine Transaminase / Q000096:biosynthesis*
chemical_list: D000596:Amino Acids; D007527:Isoenzymes; D014364:Tryptophan; D014444:Tyrosine Transaminase