Resonance assignment of the ribosome binding domain of E-coli ribosomal protein S1
Resonance assignment of the ribosome binding domain of E-coli ribosomal protein S1
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DOI：
10.1007/s12104-014-9554-2
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发表时间：
2015-04-01
影响因子：
0.9
通讯作者：
Sizun, Christina
中科院分区：
文献类型：
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作者：
Giraud, Pierre;Crechet, Jean-Bernard;Sizun, Christina
核糖体蛋白S1是大肠杆菌蛋白质合成的重要因子。它参与30 S核糖体亚基的mRNA募集和翻译起始过程中正确起始密码子的识别。E. coli S1是一个模块化蛋白，包含六个重复的S1基序，尽管结构同源，但具有不同的功能。尽管三个中心重复序列已被证明参与mRNA识别，但构成S1 N端结构域的前两个重复序列负责与30 S亚基结合。在这里，我们报告了几乎完整的H-1，C-13和N-15共振分配的两个片段的30 S结合区的S1。第一片段仅包含第一重复序列。第二个对应于整个核糖体结合结构域。由于S1是不存在的所有高分辨率的原核核糖体的X-射线结构，这些数据提供了第一步原子水平的结构表征，该域的NMR。化学位移分析的第一个重复序列提供了证据，从典型的OB-倍的S1基序的结构分歧。相反，第二个域显示预期的拓扑结构的S1基序，合理化的两个子域的功能专业化。
Ribosomal protein S1 is an essential actor for protein synthesis in Escherichia coli. It is involved in mRNA recruitment by the 30S ribosomal subunit and recognition of the correct start codon during translation initiation. E. coli S1 is a modular protein that contains six repeats of an S1 motif, which have distinct functions despite structural homology. Whereas the three central repeats have been shown to be involved in mRNA recognition, the two first repeats that constitute the N-terminal domain of S1 are responsible for binding to the 30S subunit. Here we report the almost complete H-1, C-13 and N-15 resonance assignment of two fragments of the 30S binding region of S1. The first fragment comprises only the first repeat. The second corresponds to the entire ribosome binding domain. Since S1 is absent from all high resolution X-ray structures of prokaryotic ribosomes, these data provide a first step towards atomic level structural characterization of this domain by NMR. Chemical shift analysis of the first repeat provides evidence for structural divergence from the canonical OB-fold of an S1 motif. In contrast the second domain displays the expected topology for an S1 motif, which rationalizes the functional specialization of the two subdomains.