Ogasawara T, Ito K, Igarashi K, Yutsudo T, Nakabayashi N, Takeda Y
Faculty of Pharmaceutical Sciences, Chiba University, Japan.
Microb Pathog. 1988 Feb;4(2):127-35. doi: 10.1016/0882-4010(88)90054-x.
A Vero toxin (VT2 or Shiga-like toxin II) from Escherichia coli O157:H7 was shown to inhibit protein synthesis in a rabbit reticulocyte lysate, but not in wheat germ or Ercherichia coli lysates. The toxin, VT2, inactivated 60S ribosomal subunits of rabbit reticulocytes. The site of inhibition of protein synthesis by VT2 was shown to be elongation factor 1-dependent aminoacyl-tRNA binding to ribosomes. VT2 did not affect Met-tRNAf binding to ribosomes, non-enzymatic binding of aminoacyl-tRNA to ribosomes, peptide bond formation or translocation.
来自大肠杆菌O157:H7的维罗毒素（VT2或志贺样毒素II）在兔网织红细胞裂解物中可抑制蛋白质合成，但在麦胚或大肠杆菌裂解物中则无此作用。毒素VT2可使兔网织红细胞的60S核糖体亚基失活。研究表明，VT2对蛋白质合成的抑制位点是依赖延伸因子1的氨酰tRNA与核糖体的结合。VT2不影响甲硫氨酰-tRNAf与核糖体的结合、氨酰tRNA与核糖体的非酶促结合、肽键形成或转位。
