SCREENING FOR DEFECTS OF BRANCHED-CHAIN AMINO-ACID-METABOLISM
SCREENING FOR DEFECTS OF BRANCHED-CHAIN AMINO-ACID-METABOLISM
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DOI：
10.1007/bf02138780
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发表时间：
1994-01-01
影响因子：
3.6
通讯作者：
HOFFMANN, GF
中科院分区：
文献类型：
--
作者：
GIBSON, KM;LEE, CF;HOFFMANN, GF
支链氨基酸代谢缺陷的筛查是一个连续的过程，涉及患者的临床评估、血浆肉碱测定、尿液有机酸分析以及培养或分离的外周细胞的酶研究。本报告将总结可用于诊断支链氨基酸代谢更常见缺陷的临床和代谢特征以及酶学方法，包括异戊酰辅酶A脱氢酶缺乏症、3-甲基巴豆酰辅酶A羧化酶缺乏症、3-甲基戊二酰辅酶A水合酶缺乏引起的3-甲基戊二酸尿症和其他不太明确的缺陷、3-羟基-3-甲基戊二酰辅酶A裂合酶缺乏、和 2-甲基乙酰乙酰辅酶A硫解酶缺乏症。描述了利用 (NaHCO3)-C-14 固定偶联测定的较新的酶学方法，该方法允许估计 L-亮氨酸和 L-异亮氨酸分解代谢途径中的六种酶活性。这些偶联测定有助于快速鉴定上述六种酶异常中的五种。它们易于使用，可以在任何筛查先天性代谢缺陷的实验室中实施。
Screening for defects of branched-chain amino acid metabolism is a sequential process involving clinical evaluation of the patient, plasma carnitine determination, urinary organic acid analysis, and enzyme studies in cultured or isolated peripheral cells. This report will summarize clinical and metabolite features and enzymological methods available for the diagnosis of the more common defects of branched-chain amino acid metabolism, including isovaleryl-CoA dehydrogenase deficiency, 3-methylcrotonyl-CoA carboxylase deficiency, 3-methylglutaconic aciduria due to 3-methylglutaconyl-CoA hydratase deficiency and other less well characterized defects, 3-hydroxy-3-methylglutaryl-CoA lyase deficiency, and 2-methylacetoacetyl-CoA thiolase deficiency. Newer enzymatic methodologies utilizing (NaHCO3)-C-14 fixation coupled assays are described which allow for the estimation of six enzyme activities in the catabolic pathways of L-leucine and L-isoleucine catabolism. These coupled assays facilitate the rapid identification of five of the six enzyme abnormalities described above. Their ease of use should allow them to be implemented in any laboratory which screens for inborn errors of metabolism.