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:1977
卷号:74
期号:8
页码:3264-3267
DOI:10.1073/pnas.74.8.3264
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Alterations of the structure of EF-Tu have been investigated by using the rate of EF-Tu cleavage by trypsin as a conformational probe. The presence of EF-Ts bound to EF-Tu results in a 10-fold increase in the cleavage rate. The antibiotic kirromycin, which inhibits protein synthesis by virtue of its interaction with EF-Tu, mimics this effect of EF-Ts. Both kirromycin and EF-Ts also facilitate the exchange of free GDP with GDP bound to EF-Tu. The results suggest that EF-Ts and kirromycin induce a similar conformational change in EF-Tu, thereby "opening" the guanine nucleotide binding site. The trypsin-cleaved EF-Tu still can bind GDP and EF-Ts and can function in Qbeta replicase, but it no longer spontaneously renatures following denaturation in urea.