| Popis: |
A codon-specific change in the function of transfer RNA from Escherichia coli was found in cells infected with phage Qβ. In a tRNA-dependent, cell-free system for protein synthesis, tRNA preparations from infected cells showed a markedly decreased ability to support translation of polycytidylic acid into polypeptide, as compared to tRNA from uninfected cells. However, tRNA from infected cells supported polyuridylic acid-directed phenylalanine incorporation equally as well as tRNA from uninfected cells. Ribosomal binding studies of prolyl-tRNA in response to polycytidylic acid showed that tRNA from infected cells had 2 to 3 times less ability to bind ribosomes. These results suggest that the decreased ability of tRNA from infected cells to support polycytidylic acid translation is related to the decrease in ribosomal binding of the prolyl-tRNA. |
