Translation initiation factor 3 (IF3) is one of the three protein factors that bind to the small ribosomal subunit and it is required for the initiation of protein biosynthesis in bacteria. IF3 contains two independent domains, N- and C-terminal domains, which are connected by a lysine-rich interdomain linker. IF3 undergoes large-scale movements and conformational changes upon binding to the 30S subunit and also during the functional regulation of initiation. However, the precise dynamic interplay of the two domains and the molecular mechanism of IF3 is not well understood. A high-resolution 3D structure of a complete IF3 in bacteria has not been solved. Pseudomonas aeruginosa, a gram-negative opportunistic pathogen, is a primary cause of nosocomial infections in humans. Here we report the NMR chemical shift assignments of IF3 from P. aeruginosa as the first step toward NMR structure determination and interaction studies. Secondary structure analyses deduced from the NMR chemical shift data identified nine β-strands and four α-helices arranged in the sequential order β1-β2-α1-β3-β4-α2-β5-α3-β6-α4-β7-β8-β9.

中文翻译：

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铜绿假单胞菌翻译起始因子3的1 H，13 C和15 N共振分配

翻译起始因子3（IF3）是与小核糖体亚基结合的三种蛋白质因子之一，是细菌中蛋白质生物合成起始所必需的。IF3包含两个独立的域，即N端域和C端域，它们通过富含赖氨酸的域间连接子相连。IF3在与30S亚基结合后以及在启动的功能调节过程中会发生大规模运动和构象变化。但是，这两个域的精确的动态相互作用和IF3的分子机理尚不十分清楚。细菌中完整IF3的高分辨率3D结构尚未解决。铜绿假单胞菌革兰氏阴性机会病原体是人类医院感染的主要原因。在这里，我们报告了来自铜绿假单胞菌IF3的NMR化学位移分配，这是迈向NMR结构确定和相互作用研究的第一步。从NMR化学位移数据推导的二级结构分析确定了9个β链和4个按顺序排列的1-α-螺旋β1-β2-α1-β3-β4-α2-β5-α3-β6-α4-β7-β8-β9 。