期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1973
卷号：70
期号：12
页码：3561-3565
DOI：10.1073/pnas.70.12.3561
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：N-Acetyl-Phe-tRNA, nonenzymically bound to the acceptor site of Escherichia coli ribosomes, readily undergoes translocation in the presence of elongation factor (EF)-G and GTP. The translocated N-acetyl-Phe-tRNA, bound to the ribosomal donor site, prevents further interaction of EF-G with the ribosome, for it inhibits the GTP hydrolysis that takes place in the presence of EF-G and ribosomes and it decreases the formation of either the GDP{middle dot}EF-G{middle dot}fusidic acid{middle dot}ribosome complex or the 5'-guanylylmethylenediphosphonate{middle dot}EF-G{middle dot}ribosome complex. Deacylation with puromycin of the donor site-bound N-acetyl-Phe-tRNA reverses these inhibitions, even though the tRNAPhe moiety remains bound to the ribosme. These results suggest that ribosomes complexed with messenger RNA and peptidyl-tRNA may be restricted in their ability to interact with EF-G to that part of the elongation cycle when peptidyl-tRNA is in the acceptor site, and deacylated tRNA in the donor site. Deacylation of the donor site-bound peptidyl-tRNA associated with peptide bond formation may control the interaction of EF-G with the ribosome.
