A study of highly purified mucolipidosis III urinary N-acetyl-beta-D-hexosaminidase B.
A study of highly purified mucolipidosis III urinary N-acetyl-beta-D-hexosaminidase B.
复制标题
高纯度粘脂沉积症 III 尿 N-乙酰-β-D-己糖胺酶 B 的研究。
DOI：
10.1042/bj2040557
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发表时间：
1982
期刊：
影响因子：
--
通讯作者：
Miller,AL
中科院分区：
文献类型：
--
作者：
Hirani,S;Little,L;Miller,AL
从正常尿和粘脂沉积症III患者尿中高度纯化的N-乙酰基-β-D-氨基己糖苷酶B用于确定其是否经历了与该遗传缺陷相关的任何改变。十二烷基硫酸钠/聚丙烯酰胺凝胶电泳检查表明，这两种酶制剂含有蛋白质组分的表观Mr值为55 000和28 000。未检测到正常和粘脂沉积症III酶与伴刀豆球蛋白A的结合和表观KI（50%）存在差异。然而，患者的N-乙酰-β-D-氨基己糖苷酶B对蓖麻凝集素的亲和力略高于正常酶。相应的正常和患者的N-乙酰-β-D-氨基己糖苷酶B亚基的二维胰蛋白酶肽图谱显示出相当大的同源性。这些结果表明，N-乙酰基-β-D-氨基己糖苷酶B不经历粘脂沉积症III中其他酸性水解酶所特有的显著碳水化合物改变。
Highly purified N-acetyl-beta-D-hexosaminidase B from normal urine and urine of a patient with mucolipidosis III was used to determine whether it has undergone any of the alterations associated with this genetic defect. Examination by sodium dodecyl sulphate/polyacrylamide gel electrophoresis showed that both the enzyme preparations contained protein components with apparent Mr values of 55 000 and 28 000. No differences in the binding and apparent KI (50%) to concanavalin A of the normal and mucolipidosis III enzymes were detected. However, the patient's N-acetyl-beta-D-hexosaminidase B had a slightly greater affinity for the lectin from Ricinus communis than did the normal enzyme. Two-dimensional tryptic peptide maps of the corresponding normal and the patient's N-acetyl-beta-D-hexosaminidase B subunits showed considerable homology. These results indicate that N-acetyl-beta-D-hexosaminidase b does not undergo the significant carbohydrate alterations characteristic of other acid hydrolases in mucolipidosis III.