一种用于检测人成纤维细胞中天冬氨酸酰基转移酶活性的放射测定法：在卡纳万病诊断中的应用。

A radiometric assay for aspartoacylase activity in human fibroblasts: application for the diagnosis of Canavan's disease.

作者信息

Barash V, Flhor D, Morag B, Boneh A, Elpeleg O N, Gilon C

机构信息

Department of Clinical Biochemistry, Hadassah University Hospital, Jerusalem, Israel.

出版信息

Clin Chim Acta. 1991 Sep 30;201(3):175-81. doi: 10.1016/0009-8981(91)90368-m.

DOI:10.1016/0009-8981(91)90368-m

PMID:1756590

Abstract

A new sensitive method for measuring aspartoacylase activity in human skin fibroblasts using [3H]N-acetyl-L-aspartic acid (NAA) is described. Optimal assay conditions and kinetic parameters for enzyme activity were determined. The enzyme was found to have maximal activity at pH 8.5, and the Michaelis constant for the substrate N-acetylaspartate was 1.8-2.0 mmol/l. Aspartoacylase activity in control cultured human fibroblasts was 9.2 +/- 1.8 nmol/h per mg protein, compared with 1.1 +/- 0.2 in seven Canavan patients and 3.5 +/- 0.9 in four patients' parents. This method for determining aspartoacylase activity is advantageous to the previously described spectrophotometric method since it is rapid, more sensitive and has less nonspecific interference. It is possible that application of this technique to cultured ammniotic and chorionic villi cells may be used for prenatal diagnosis of Canavan's disease.

摘要

本文描述了一种使用[3H]N-乙酰-L-天冬氨酸（NAA）测量人皮肤成纤维细胞中天冬氨酸酰基转移酶活性的新的灵敏方法。确定了酶活性的最佳测定条件和动力学参数。发现该酶在pH 8.5时具有最大活性，底物N-乙酰天冬氨酸的米氏常数为1.8 - 2.0 mmol/l。对照培养的人成纤维细胞中天冬氨酸酰基转移酶活性为每毫克蛋白质9.2±1.8 nmol/h，而7例卡纳万病患者中该活性为1.1±0.2，4例患者父母中该活性为3.5±0.9。这种测定天冬氨酸酰基转移酶活性的方法比先前描述的分光光度法更具优势，因为它快速、更灵敏且非特异性干扰更少。将该技术应用于培养的羊膜和绒毛膜绒毛细胞有可能用于卡纳万病的产前诊断。