A Sensitive Fluorometric Determination of Erythrocyte and Serum Argininosuccinate Lyase Activities with 2, 3-Naphthalenedicarbaldehyde

Abstract

A sensitive fluorometric method was developed for the determination of erythrocyte and serum argininosuccinate lyases (EC 4.3.2.1) which are useful marker enzymes in a diagnosis of argininosuccinic aciduria and hepatitis, respectively. Arginine, liberated from argininosuccinate in the lyase-mediated reaction, was determined by a specific fluorescence reaction with 2, 3-naphthalenedicarbaldehyde. This method is simple and requires smaller amounts of erythrocyte and serum samples. The enzyme activities in erythrocyte and serum from normal volunteers were 88.5±14.3mU/g hemoglobin (mean±SD, n=10) and below 0.26mU/ml serum (n=7). The activities in sera from patients with liver diseases were also measured.