Conformational change in the catalytic site of the ribonuclease YoeB toxin by YefM antitoxin
Conformational change in the catalytic site of the ribonuclease YoeB toxin by YefM antitoxin
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DOI：
10.1016/j.molcel.2005.07.004
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发表时间：
2005-08-19
期刊：
影响因子：
16
通讯作者：
Hanaoka, F
中科院分区：
文献类型：
--
作者：
Kamada, K;Hanaoka, F
真细菌染色体编码各种成瘾模块，这些模块通过RNA降解控制全球翻译水平。测定了大肠杆菌YefM(2)(抗毒素)-YoeB(毒素)络合物和游离YoeB毒素的晶体结构。异三聚体复合体的结构揭示了一种不对称的无序有序识别策略，在该策略中，YefM同源二聚体的C端仅与YoeB的非典型微生物核糖核酸酶(RNase)折叠相互作用。与不含YefM的YoeB结构的比较表明，YoeB的核糖核酸酶催化位发生了构象重排，这是由于YefM与YefM相互作用引起的。互补生化实验表明，YoeB毒素在体外具有核糖核酸酶活性，优先切割在嘌呤核苷酸的3‘端。
The eubacterial chromosome encodes various addiction modules that control global levels of translation through RNA degradation. Crystal structures of the Escherichia coli YefM(2) (antitoxin)-YoeB (toxin) complex and the free YoeB toxin have been determined. The structure of the heterotrimeric complex reveals an asymmetric disorder-to-order recognition strategy, in which one C terminus of the YefM homodimer exclusively interacts with an atypical microbial ribonuclease (RNase) fold of YoeB. Comparison with the YefM-free YoeB structure indicates a conformational rearrangement of the RNase catalytic site of YoeB, induced by interaction with YefM. Complementary biochemical experiments demonstrate that the YoeB toxin has an in vitro RNase activity that preferentially cleaves at the 3' end of purine ribonucleotides.