Warner T G, Louie A, Potier M
Department of Pediatrics, University of Tennessee, Memphis.
Biochem Biophys Res Commun. 1990 Nov 30;173(1):13-9. doi: 10.1016/s0006-291x(05)81014-9.
Photolabeling of the alpha-neuraminidase/beta-galactosidase complex in human placenta (Verheijen, F.W. et al (1987) Eur. J. Biochem. 162, 63-67) was carried out using the radioactive photoprobe, 9-S-(4-azido-3,5-3H-2-nitrophenyl)-5-acetamido-2,6 anhydro-2,3,5,9- tetradeoxy-9- thio-D-glycero-D-galacto-non-2-enonic acid. Two intensely labeled bands at 61 and 46 kD were detected with autoradiography. Labeling of the 46 kD protein was blocked with the inclusion of the surfactant Triton X-100 in the photolysis mixture, indicating a nonspecific, hydrophobic interaction. The 61 kD protein was protected from labeling only when the neuraminidase inhibitor 2,3 dehydro N-acetyl neuraminic acid (1 mM) was present during photolysis. These results suggest that the neuraminidase activity resides among the proteins in the 61 kD molecular weight range comigrating with the lysosomal beta-galactosidase, under denaturing conditions.
使用放射性光探针9-S-(4-叠氮基-3,5-³H-2-硝基苯基)-5-乙酰氨基-2,6-脱水-2,3,5,9-四脱氧-9-硫代-D-甘油-D-半乳糖-壬-2-烯酸，对人胎盘（Verheijen, F.W.等人（1987年），《欧洲生物化学杂志》162卷，63 - 67页）中的α-神经氨酸酶/β-半乳糖苷酶复合物进行光标记。放射自显影检测到61 kD和46 kD处有两条强烈标记的条带。在光解混合物中加入表面活性剂Triton X-100后，46 kD蛋白的标记被阻断，这表明存在非特异性的疏水相互作用。只有在光解过程中存在神经氨酸酶抑制剂2,3-脱氢-N-乙酰神经氨酸（1 mM）时，61 kD蛋白才会免受标记。这些结果表明，在变性条件下，神经氨酸酶活性存在于与溶酶体β-半乳糖苷酶共迁移的61 kD分子量范围内的蛋白质中。
