Assay of the Enzymes of Pyrimidine Synthesis by Thin Layer Ion Exchange Chromatography and Video-Densitometry (CV-Technique)

Abstract

A simple and rapid method is described for the assay of the glutamine-dependent carbamoyl phosphate synthetase and aspartate carbamoyltransferase in minute amounts of liver tissue. From 60–120 μl assay mixtures 10–20 μl aliquots were chromatographed on thin layer ion exchange chromatoplates, and the amino acids were developed with ninhydrin. The intensity of the ninhydrin spots, i.e. the quantity of amino acids formed or consumed, was determined by video-densitometry and the specific activity of the enzymes was calculated.