The ribosome is an ancient and universally conserved macromolecular machine that synthesizes proteins in all organisms. Since the discovery of the ribosome by electron microscopy in the mid-1950s, rapid progress has been made in research on it, regarding its architecture and functions. As a machine that synthesizes polypeptides, the sequential addition of amino acids to a growing polypeptide chain occurs during a phase called the elongation cycle. This is the core step of protein translation and is highly conserved between bacteria and eukarya. The elongation cycle involves codon recognition by aminoacyl tRNAs, catalysis of peptide bond formation, and the most complex operation of translation—translocation. In this review, we discuss the fundamental results from structural and functional studies over the past decades that have led to understanding of the three key questions underlying translation.

中文翻译：

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结构和功能研究揭示了蛋白质翻译延伸步骤的关键机制。

核糖体是一种古老且普遍保存的大分子机器，可在所有生物体中合成蛋白质。自从1950年代中期通过电子显微镜发现核糖体以来，关于核糖体的结构和功能的研究已经取得了迅速的进展。作为合成多肽的机器，将氨基酸顺序添加到生长中的多肽链上的过程称为伸长循环。这是蛋白质翻译的核心步骤，在细菌和真核生物之间是高度保守的。延长周期涉及氨酰基tRNA的密码子识别，肽键形成的催化作用以及翻译-易位的最复杂操作。在这篇评论中