Goldstein J, Champe S P
J Virol. 1974 Feb;13(2):419-27. doi: 10.1128/JVI.13.2.419-427.1974.
We have examined the acid-soluble products formed during incubation of labeled substrate protein from T4-infected cells with unlabeled phage-infected cell extracts. If the substrate protein is prepared from cells infected with a T4 mutant blocked in cleavage of phage head precursor proteins, the products formed in vitro include a peptide indistinguishable by several criteria from one of the T4 internal peptides. Denatured as well as undenatured protein can serve as the substrate for the formation of this peptide. As expected, this peptide is not formed if protein from either uninfected cells or cells infected with wild-type T4 is used as substrate. The formation of this peptide in vitro is dependent on a factor present in extracts of phage-infected cells but absent from extracts of uninfected cells.
我们检测了用未标记的噬菌体感染细胞提取物孵育来自T4感染细胞的标记底物蛋白时形成的酸溶性产物。如果底物蛋白是从感染了在噬菌体头部前体蛋白切割中受阻的T4突变体的细胞中制备的，那么体外形成的产物包括一种在几个标准上与T4内部肽之一无法区分的肽。变性蛋白和未变性蛋白都可以作为形成这种肽的底物。正如预期的那样，如果使用来自未感染细胞或感染野生型T4的细胞的蛋白作为底物，则不会形成这种肽。这种肽在体外的形成依赖于噬菌体感染细胞提取物中存在但未感染细胞提取物中不存在的一种因子。
