Caskey C T, Beaudet A L, Scolnick E M, Rosman M
Proc Natl Acad Sci U S A. 1971 Dec;68(12):3163-7. doi: 10.1073/pnas.68.12.3163.
Escherichia coli and rabbit reticulocyte (f[(3)H]Met-tRNA.AUG.ribosome) intermediates undergo hydrolysis, with release of f[(3)H]methionine, upon addition of tRNA or CpCpA in the presence of acetone. This ribosomal catalyzed reaction has similar requirements, pH optimum, and antibiotic sensitivity to those of peptidyl transferase. Two antibiotics, lincomycin with E. coli ribosomes and anisomycin with reticulocyte ribosomes, inhibit peptide-bond formation and transesterification activities of peptidyl transferase, but stimulate hydrolysis of f[(3)H]Met-tRNA. Earlier studies have suggested peptidyl transferase activity is essential for R factor-dependent hydrolysis of f((3)H)Met-tRNA. These studies indicate that peptidyl transferase has the capacity for f((3)H)Met-tRNA hydrolysis and, therefore, may be responsible for peptidyl-tRNA cleavage during peptide chain termination.
在丙酮存在的情况下，加入tRNA或CpCpA后，大肠杆菌和兔网织红细胞（f[(3)H]甲硫氨酸 - tRNA·AUG·核糖体）中间体发生水解，释放出f[(3)H]甲硫氨酸。这种核糖体催化的反应与肽基转移酶的反应具有相似的要求、最适pH值和抗生素敏感性。两种抗生素，即与大肠杆菌核糖体作用的林可霉素和与网织红细胞核糖体作用的茴香霉素，抑制肽基转移酶的肽键形成和转酯活性，但刺激f[(3)H]甲硫氨酸 - tRNA的水解。早期研究表明，肽基转移酶活性对于R因子依赖性的f((3)H)甲硫氨酸 - tRNA水解至关重要。这些研究表明，肽基转移酶具有f((3)H)甲硫氨酸 - tRNA水解能力，因此可能在肽链终止过程中负责肽基 - tRNA的切割。
