Yutaka T, Kato T, Midorikawa M, Doke M, Okada S, Yabuuchi H
Clin Chim Acta. 1984 Feb 28;137(2):159-68. doi: 10.1016/0009-8981(84)90176-1.
We have prepared a new radiolabeled substrate (N-[3H]acetylglucosamine-glucuronic acid-N-[3H]acetylglucosamine), from hyaluronic acid, for an assay of beta-N-acetylhexosaminidase activity. Using this substrate, we found a striking deficiency of beta-N-acetylhexosaminidase activity in cultured skin fibroblasts and in liver homogenates from patients with Tay-Sachs disease. DEAE-cellulose chromatography at pH 6.0 revealed that both isoenzymes A and B of beta-N-acetylhexosaminidase from normal liver participated in the catabolism of hyaluronic acid. There were, however, major differences in substrate specificities between isoenzymes A and B. Our results indicate that this substrate should be useful for enzymatic diagnosis of Tay-Sachs disease.
我们从透明质酸制备了一种新的放射性标记底物（N-[³H]乙酰葡糖胺 - 葡糖醛酸 - N-[³H]乙酰葡糖胺），用于检测β-N-乙酰己糖胺酶活性。使用这种底物，我们发现患有泰 - 萨克斯病的患者的培养皮肤成纤维细胞和肝脏匀浆中β-N-乙酰己糖胺酶活性显著缺乏。在pH 6.0条件下进行的二乙氨基乙基纤维素色谱分析表明，正常肝脏中β-N-乙酰己糖胺酶的同工酶A和B都参与了透明质酸的分解代谢。然而，同工酶A和B之间的底物特异性存在主要差异。我们的结果表明，这种底物应该有助于泰 - 萨克斯病的酶学诊断。
