Cavanagh D, Sangar D V, Rowlands D J, Brown F
J Gen Virol. 1977 Apr;35(1):149-58. doi: 10.1099/0022-1317-35-1-149.
Chymotrypsin cleaves only one of the four major polypeptides of foot-and-mouth disease virus (FMDV serotype O) in situ. This polypeptide (VP1, mol. wt. 29 X 10(3) was first cleaved into fragments of mol. wt. 20 and 9 X 10(3) and further cleavage could be prevented by the addition of a large excess of bovine serum albumin. The infectivity of the virus particles at this stage was the same as that of the intact virus although the rate of attachment to BHK 21 cells was slower and the immunogenic activity was reduced. If hydrolysis was allowed to continue, VP1 was cleaved into fragments with mol. wt. 18 and less than 9 X 10(3), similar to those obtained with trypsin and the virus particles then had a greatly reduced infectivity and a lower immunogenicity. Treatment of strains from five other serotypes of the virus with the two enzymes cleaved only VP1 in each instance and there was a corresponding loss of infectivity. The results are discussed in relation to the location and biological activity of the virus polypeptides.
胰凝乳蛋白酶仅在原位切割口蹄疫病毒（O型口蹄疫病毒血清型）的四种主要多肽中的一种。这种多肽（VP1，分子量29×10³）首先被切割成分子量为20×10³和9×10³的片段，通过添加大量过量的牛血清白蛋白可以防止进一步切割。尽管此时病毒颗粒与BHK 21细胞的附着速率较慢且免疫原活性降低，但其感染性与完整病毒相同。如果继续水解，VP1会被切割成分子量为18×10³及小于9×10³的片段，类似于用胰蛋白酶处理后得到的片段，此时病毒颗粒的感染性大大降低且免疫原性也较低。用这两种酶处理该病毒其他五种血清型的毒株，在每种情况下仅切割VP1，并且伴随着相应的感染性丧失。结合病毒多肽的位置和生物学活性对结果进行了讨论。
