Institute for Microbiology and Genetics, Justus-von-Liebig Weg 11, Georg-August University Göttingen, 37077 Göttingen, Germany.
FEBS Lett. 2012 Jul 16;586(15):2057-64. doi: 10.1016/j.febslet.2012.02.002. Epub 2012 Feb 13.
With few minor variations, the genetic code is universal to all forms of life on our planet. It is difficult to imagine that one day organisms might exist that use an entirely different code to translate the information of their genome. Recent developments in the field of synthetic biology, however, have opened the gate to their creation. The genetic code of several organisms has been expanded by the heterologous expression of evolved aminoacyl-tRNA synthetase/tRNA(CUA) pairs that mediate the incorporation of unnatural amino acids in response to amber codons. These UAAs introduce exciting new features into proteins, such as spectroscopic probes, UV-inducible crosslinkers, and functional groups for bioorthogonal conjugations or posttranslational modifications. Orthogonal ribosomes provide a parallel translational machinery in Escherichia coli that has lost its evolutionary constraints. Evolved variants of these ribosomes translate amber or quadruplet codons with massively enhanced efficiency. Here, I review these recent developments emphasizing their tremendous potential to facilitate biochemical and cell biological studies.
除了少数微小的变化，地球上所有生命形式的遗传密码都是通用的。很难想象有一天会存在使用完全不同的密码来翻译基因组信息的生物体。然而，合成生物学领域的最新发展为创造这样的生物体打开了大门。通过异源表达进化的氨酰-tRNA 合成酶/tRNA(CUA)对，可以扩展几种生物体的遗传密码，这些对介导非天然氨基酸在琥珀终止密码子的掺入。这些非天然氨基酸为蛋白质引入了令人兴奋的新特性，例如光谱探针、紫外线诱导的交联剂以及用于生物正交共轭或翻译后修饰的官能团。正交核糖体为失去进化限制的大肠杆菌提供了一种平行的翻译机制。这些核糖体的进化变体以极高的效率翻译琥珀或四联体密码子。在这里，我回顾了这些最新的发展，强调了它们在促进生化和细胞生物学研究方面的巨大潜力。
