Potier M, Lamontagne S, Michaud L, Tranchemontagne J
Service de Génétique Médicale, Hôpital Sainte-Justine, Université de Montréal, Québec, Canada.
Biochem Biophys Res Commun. 1990 Nov 30;173(1):449-56. doi: 10.1016/s0006-291x(05)81079-4.
Human neuraminidase was purified from placenta as part of a large molecular weight complex with lysosomal beta-galactosidase and carboxypeptidase. Passage of this purified complex through a sialic acid-affinity column (fetuin-agarose) retained a minor 60 kDa protein which was eluted with 100 mM N-acetylneuraminic acid. This 60 kDa protein is recognized in Western blots of the purified complex by an anti-prosaposin antibody which at the same time was able to inhibit neuraminidase activity in the preparation. Furthermore, probing of cultured skin fibroblasts of patients affected with neuraminidase deficiency using the antiprosaposin antibody revealed an abnormal 57 kDa protein. These results indicate that the 60 kDa protein is derived from prosaposin and has the characteristics of a neuraminidase.
人神经氨酸酶是从胎盘中纯化出来的，它是一种与溶酶体β-半乳糖苷酶和羧肽酶形成的大分子复合物的一部分。这种纯化的复合物通过唾液酸亲和柱（胎球蛋白-琼脂糖）后，保留了一种分子量为60 kDa的次要蛋白质，该蛋白质可用100 mM N-乙酰神经氨酸洗脱。在纯化复合物的蛋白质免疫印迹中，这种60 kDa的蛋白质可被抗前体蛋白聚糖抗体识别，同时该抗体能够抑制制剂中的神经氨酸酶活性。此外，用抗前体蛋白聚糖抗体检测神经氨酸酶缺乏症患者的培养皮肤成纤维细胞，发现了一种异常的57 kDa蛋白质。这些结果表明，60 kDa的蛋白质源自前体蛋白聚糖，并具有神经氨酸酶的特性。
