N-Acetylglutamate Synthetase: Enzyme Assay in Human Liver

Abstract

In the context of diagnostic procedures for congenital hyperammonaemias a methods is described for the determination of N-acetylglutamate synthetase in human liver tissue homogenates. The method uses [14C-U] glutamate and acetyl CoA as substrates. The reaction product, N-acetylglutamate is separated from the substrate L-glutamate by chromatography on Extrelut. In a subsequent step on ITLC-SG ready plates N-acetylglutamate is separated from other labeled metabolites such as Krebs cycle intermediates. The recovery of N-acetylglutamate was 97.8%. The precision within run and between days was 8.5% (CV) and 9.6% (CV) respectively. Reference values were established for adult human liver.