Translational GTPases (trGTPases) belong to the family of G proteins and play key roles at all stages of protein biosynthesis on the ribosome. Unidirectional and cyclic functioning of G proteins is ensured by their ability to switch between the active and inactive states due to GTP hydrolysis accelerated by the auxiliary GTPase-activating proteins. Although trGTPases interact with the ribosomes in different conformational states, they bind to the same conserved region, which, unlike in classical GTPase-activating proteins, is represented by ribosomal RNA. The resulting catalytic sites have almost identical structure in all elongation factors suggesting a common mechanism of GTP hydrolysis. However, fine details of the activated state formation and significantly different rates of GTP hydrolysis indicate the existence of distinctive features upon GTP hydrolysis catalyzed by the different factors. Here, we present a contemporary view on the mechanism of GTPase activation and GTP hydrolysis by the elongation factors EF-Tu, EF-G, and SelB based on the analysis of structural, biochemical, and bioinformatics data.

中文翻译：

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伸长因子水解活性活化的特点

翻译 GTP 酶 (trGTPases) 属于 G 蛋白家族，在核糖体上蛋白质生物合成的所有阶段都起着关键作用。由于辅助 GTPase 激活蛋白加速了 GTP 水解，G 蛋白能够在活性和非活性状态之间切换，从而确保 G 蛋白的单向和循环功能。尽管 trGTPases 与处于不同构象状态的核糖体相互作用，但它们与相同的保守区域结合，与经典的 GTPase 激活蛋白不同，该区域由核糖体 RNA 表示。由此产生的催化位点在所有延伸因子中具有几乎相同的结构，表明 GTP 水解的共同机制。然而，激活态形成的细节和 GTP 水解速率的显着差异表明在不同因素催化的 GTP 水解中存在独特的特征。在这里，我们基于对结构、生化和生物信息学数据的分析，提出了关于伸长因子 EF-Tu、EF-G 和 SelB 的 GTPase 激活和 GTP 水解机制的当代观点。