核糖体按照信使RNA指定的氨基酸序列来构建蛋白质。在这里,研究人员设计、合成了一个小分子机器,该机器沿着的分子链按照序列特异性方式进行多肽合成。该小分子机器的化学结构是基于一个轮烷,分子环拧到一个分子桥。环带有硫醇盐基团,可以反复按照特定顺序删除氨基酸,并将它们运送到的多肽 生长延长位点。实验结果表明大约有10 18 的小分子机器在并行进行合成;这一过程会产生毫克量级多肽。串联质谱实验确认只产生了单一多肽序列。 英文全文见: http://www.sciencemag.org/content/339/6116/189.full Sequence-Specific Peptide Synthesis by an Artificial Small-Molecule Machine Bartosz Lewandowski 1 , Guillaume De Bo 1 , John W. Ward 1 , Marcus Papmeyer 1 , Sonja Kuschel 1 , María J. Aldegunde 2 , Philipp M. E. Gramlich 2 , Dominik Heckmann 2 , Stephen M. Goldup 2 , Daniel M. D’Souza 2 , Antony E. Fernandes 2 , David A. Leigh 1 , 2 , * The ribosome builds proteins by joining together amino acids in an order determined by messenger RNA. Here, we report on the design, synthesis, and operation of an artificial small-molecule machine that travels along a molecular strand, picking up amino acids that block its path, to synthesize a peptide in a sequence-specific manner. The chemical structure is based on a rotaxane, a molecular ring threaded onto a molecular axle. The ring carries a thiolate group that iteratively removes amino acids in order from the strand and transfers them to a peptide-elongation site through native chemical ligation. The synthesis is demonstrated with ~10 18 molecular machines acting in parallel; this process generates milligram quantities of a peptide with a single sequence confirmed by tandem mass spectrometry.