通过完整成纤维细胞中瓜氨酸向精氨酸的转化检测新生儿瓜氨酸血症中动力学异常的精氨琥珀酸合成酶。

Detection of kinetically abnormal argininosuccinate synthase in neonatal citrullinemia by conversion of citrulline to arginine in intact fibroblasts.

作者信息

Ben-Yoseph Y, Mitchell D A

机构信息

Department of Pediatrics, C.S. Mott Center for Human Growth and Development, Wayne State University School of Medicine, Detroit, MI 48201.

出版信息

Clin Chim Acta. 1989 Aug 15;183(2):125-33. doi: 10.1016/0009-8981(89)90328-8.

DOI:10.1016/0009-8981(89)90328-8

PMID:2791302

Abstract

The apparent Km values of argininosuccinate synthase toward citrulline and aspartate were significantly increased in cultured skin fibroblasts from one patient with neonatal citrullinemia, whereas, those determined in cells from three other patients were within the normal range. The abnormal apparent Km of the mutant enzyme toward aspartate was determined by a ureagenesis assay system (0.14 mmol/l as compared with 0.010-0.018 mmol/l for the normal enzyme), and the abnormal values toward citrulline were measured by both arginine synthesis (6.1 mmol/l as compared with 0.21-0.26 mmol/l for the normal enzyme) and ureagenesis (0.63 as compared with 0.043-0.067) assay systems.

摘要

一名新生儿瓜氨酸血症患者培养的皮肤成纤维细胞中，精氨琥珀酸合酶对瓜氨酸和天冬氨酸的表观米氏常数显著升高，而其他三名患者细胞中的该常数则在正常范围内。通过尿素生成测定系统确定突变酶对天冬氨酸的异常表观米氏常数（为0.14 mmol/L，而正常酶为0.010 - 0.018 mmol/L），并通过精氨酸合成（为6.1 mmol/L，而正常酶为0.21 - 0.26 mmol/L）和尿素生成（为0.63，而正常酶为0.043 - 0.067）测定系统测量对瓜氨酸的异常值。