López S, Arias C F, Bell J R, Strauss J H, Espejo R T
Virology. 1985 Jul 15;144(1):11-9. doi: 10.1016/0042-6822(85)90300-9.
The primary structure of the trypsin cleavage site in the outer layer protein VP3 of rotavirus SA11 was determined. This cleavage enhances the infectivity of rotavirus SA11. Both VP8, one of the polypeptides generated by the cleavage, and VP3 had their alpha-NH2 blocked. Only VP5, the other polypeptide produced by the cleavage, was susceptible to sequential Edman degradation, indicating that it contained the new alpha-NH2 terminus generated by trypsin hydrolysis. The results indicated that purified VP5 is composed of two polypeptides with the following amino acid sequence at their N terminus: (a) ??VYTRAQPNQDAVVSKTS...; (b) AQPNQDAVVSKTS.... Sequencing of the DNA complementary to ds RNA segment 4 revealed a nucleotide sequence encoding the amino acid sequences indicated above, with only one different amino acid. From these results, the amino acid sequence of the site cleaved by trypsin was extended to cover the C termini (present in VP8). The following sequence, which contains two sites (indicated with asterisks) and can be cleaved by trypsin was deduced: ... VPVSIVSRNIVYTRAQPNQDIVVSKTS....
确定了轮状病毒SA11外层蛋白VP3中胰蛋白酶切割位点的一级结构。这种切割增强了轮状病毒SA11的感染性。切割产生的多肽之一VP8和VP3的α-NH2均被封闭。只有切割产生的另一种多肽VP5易受连续的埃德曼降解作用影响，这表明它含有由胰蛋白酶水解产生的新的α-NH2末端。结果表明，纯化的VP5由两种多肽组成，它们的N末端具有以下氨基酸序列：(a) ??VYTRAQPNQDAVVSKTS...；(b) AQPNQDAVVSKTS.... 与双链RNA片段4互补的DNA测序揭示了一个编码上述氨基酸序列的核苷酸序列，只有一个不同的氨基酸。根据这些结果，将被胰蛋白酶切割的位点的氨基酸序列延伸以覆盖C末端（存在于VP8中）。推导得到以下序列，其包含两个位点（用星号表示）且可被胰蛋白酶切割：... VPVSIVSRNIVYTRAQPNQDIVVSKTS....
