Re-Evaluation of Conditions Required for Measurement of True Alanine:Glyoxylate Aminotransferase Activity in Human Liver: Implications for the Diagnosis of Hyperoxaluria Type I

Abstract

SUMMARY. In this paper we studied the glyoxy1ate-dependent transamination of Lalanine and L-glutamate in human liver homogenates in order to develop a reliable method for the determination of true alanine:glyoxylate aminotransferase activity in liver homogenates from patients suspected to suffer from hyperoxaluria type 1. Measurements were made according to two protocols described in literature in control human liver homogenates which were either untreated or treated with an antiserum raised against purified alanine:glyoxylate aminotransferase. The results obtained show that enzyme activity can best be determined at pH 8.0 as compared to pH 7.4 since the former leads to a higher sensitivity of the method. Alanine:glyoxylate aminotransferase activities measured at pH 8.0 are approximately 50070 higher compared to the enzyme activities measured at pH 7.4. Accordingly, it is proposed to measure alanine:glyoxylate aminotransferase activity at pH 8.0 using the newly determined correction factor as described in this paper.

Hepatic peroxisomes in isolated hyperpipecolic acidaemia: evidence supporting its classification as a single peroxisomal enzyme deficiency

“…Polyclonal antibodies against AGT were raised in rabbits against the purified enzyme from human liver [10]; polyclonal antibodies against acyl-CoA oxidase and bifunctional protein were raised in rabbits against the isolated enzyme from rat liver (IgG fractions obtained by ammonium sulfate precipitation); polyclonal antibodies against PMP43 kDa were raised in rabbits against the membrane from human liver peroxisomes [26].…”