文章基本信息

标题：Requirement of Proteins S5 and S9 from 30S Subunits for the Ribosome-Dependent GTPase Activity of Elongation Factor G
本地全文：下载
作者：Robert C. Marsh ; Andrea Parmeggiani
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：1
页码：151-155
DOI：10.1073/pnas.70.1.151
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：During CsCl isopycnic centrifugation at 20 mM Mg++, Escherichia coli 30S ribosomal subunits specifically lose proteins S1, S2, S3, S5, S9, S10, and S14. The resultant 30S core is unable to stimulate the GTPase activity of EF-G in the presence of 50S subunits. Activity could be restored to a small extent by adding back S2, S5, or S9. However, when S5 and S9 were added together, they cooperatively produced 30S particles 1.5 times more active than the original native 30S subunits. The small amount of activity restored by S2 was simply additive to that restored by S5 or S9. None of the other split proteins showed any restoring capability. Ability of the various protein-deficient 30S particles to couple with 50S subunits corresponded closely to their activity in the EF-G GTPase reaction. It is concluded that S5 and S9 together enable the 30S subunit to participate in the formation of a GTPase-active 30S-50S-EF-G complex.
关键词：CsCl 30S core ; ribosomal split proteins ; 30S reconstitution ; 30S-50S association