Activation of the Sendai virus fusion protein by receptor binding.
Activation of the Sendai virus fusion protein by receptor binding.
复制标题
通过受体结合激活仙台病毒融合蛋白。
DOI：
10.1006/bbrc.1995.1301
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发表时间：
1995
影响因子：
3.1
通讯作者：
T. Bellini
中科院分区：
文献类型：
--
作者：
F. Dallocchio;M. Tomasi;T. Bellini
2，3-脱氢-2-脱氧-N-乙酰神经氨酸（DNANA）竞争性抑制仙台病毒血凝素-神经氨酸酶（HN）的神经氨酸酶活性。抑制常数取决于融合（F）蛋白的存在，其在活性F蛋白存在下为30 μ M，当F蛋白失活时为50 μ M。这些数据与之前报道的F蛋白与HN相互作用的证据相关（Dallocchio，F.，Tomasi，M.，& Bellini，T.（1994）Biochem. Biophys. Res.Comm.201，988-993）。梭菌神经氨酸酶对红细胞的去水解作用使SV的溶血活性降低至未处理红细胞上观察到的溶血活性的< 0.1%。然而，DNANA的加入导致溶血活性的浓度依赖性增加。HN和F蛋白都是DNA激活溶血活性所必需的。从对去唾液酸红细胞的溶血活性的活化计算的DNANA的亲和常数为35 μ M，非常接近神经氨酸酶活性的Ki。这些数据表明，由底物或底物类似物与HN的结合诱导的F蛋白与HN的结合引起激活F蛋白的构象变化。
2,3 Dehydro-2-deoxy-N-acetyl-neuraminic acid (DNANA) competitively inhibits the neuraminidase activity of Hemagglutinin-neuraminidase (HN) from Sendai virus. The inhibition constant depends on the presence of the Fusion (F) protein, which is 30 microM in the presence of active F protein and 50 microM when the F protein is inactivated. These data correlate with previously reported evidence of interaction of the F protein with HN (Dallocchio, F., Tomasi, M., & Bellini, T. (1994) Biochem. Biophys. Res. Comm. 201, 988-993). Desialyzation of erythrocytes, by Clostridium neuraminidase, lowers the hemolytic activity of SV to < 0.1% of that observed on untreated erythrocytes. However, addition of DNANA causes a concentration-dependent increase of hemolytic activity. Both HN and the F protein are required for the activation of hemolytic activity by DNANA. The affinity constant for DNANA, calculated from the activation of hemolytic activity on desialyzed erythrocytes, is 35 microM, very close to the Ki for neuraminidase activity. These data suggest that the binding of the F protein to HN, induced by the binding to HN of a substrate or a substrate analogue, causes a conformational change which activates the F protein.