The antibiotics dityromycin and GE82832 bind protein S12 and block EF-G-catalyzed translocation.
The antibiotics dityromycin and GE82832 bind protein S12 and block EF-G-catalyzed translocation.
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DOI：
10.1016/j.celrep.2013.12.024
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发表时间：
2014-01-30
期刊：
影响因子：
8.8
通讯作者：
Steitz TA
中科院分区：
文献类型：
--
作者：
Bulkley D;Brandi L;Polikanov YS;Fabbretti A;O'Connor M;Gualerzi CO;Steitz TA
信使RNA和转运RNA通过核糖体的易位由EF-G催化，EF-G是一种普遍保守的GT3。本研究阐明了密切相关的十肽抗生素二替罗霉素和GE 82832抑制EF-G催化的易位的机制。使用晶体学和生物化学实验，我们证明，这些抗生素结合到核糖体蛋白S12在溶液中，以及在小核糖体亚基，诱导对核糖体头部的长期影响。与70 S核糖体复合的抗生素的晶体结构揭示了结合涉及S12的保守氨基酸残基，其突变导致体外和体内抗生素抗性和抗生素结合的丧失。这些数据还表明，GE 82832/dityromycin通过破坏EF-G和S12之间稳定EF-G的易位后构象所需的关键接触来抑制EF-G催化的易位，从而防止核糖体-EF-G复合物进入产生易位的构象。
The translocation of messenger RNA and transfer RNA through the ribosome is catalyzed by EF-G, a universally conserved GTPase. The mechanism by which the closely related decapeptide antibiotics dityromycin and GE82832 inhibit EF-G-catalyzed translocation is elucidated in this study. Using crystallographic and biochemical experiments we demonstrate that these antibiotics bind to ribosomal protein S12 in solution as well as within the small ribosomal subunit, inducing long-range effects on the ribosomal head. The crystal structure of the antibiotic in complex with the 70S ribosome reveals that the binding involves conserved amino acid residues of S12 whose mutations result in in vitro and in vivo antibiotic resistance and loss of antibiotic binding. The data also suggest that GE82832/dityromycin inhibits EF-G-catalyzed translocation by disrupting a critical contact between EF-G and S12 that is required to stabilize the post-translocational conformation of EF-G, thereby preventing the ribosome-EF-G complex from entering a conformation productive for translocation.