title: Comparative studies on threonine and serine dehydratases in rat liver.
abstract: 1. Two isoenzymes of serine (threonine) dehydratase can be separated by DEAE cellulose chromatography. 2. Each of these isoenzymes possesses different S:T (serine dehydratase activity: threonine dehydratase activity) ratio and kinetic properties. 3. In early postnatal development, the S:T ratio shows marked variation. 4. The hepatic S:T ratio also changes with dietary manipulations. Furthermore L-alanine inhibits enzymic activities towards serine and threonine to different extent. 5. The results are consistent with the hypothesis postulating the presence of two distinct proteins each having a different activity ratio towards serine and threonine.
mesh_terms: D000409:Alanine / Q000494:pharmacology; D000818:Animals; D004044:Dietary Proteins / Q000008:administration & dosage; D007527:Isoenzymes / Q000378:metabolism*; D012695:L-Serine Dehydratase / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism*; D008099:Liver / Q000201:enzymology*; D051381:Rats; D013217:Starvation / Q000201:enzymology; D013913:Threonine Dehydratase / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D004044:Dietary Proteins; D007527:Isoenzymes; D012695:L-Serine Dehydratase; D013913:Threonine Dehydratase; D000409:Alanine