Cathopoulis Terry, Chuawong Pitak, Hendrickson Tamara L
Department of Chemistry, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, USA.
Mol Biosyst. 2007 Jun;3(6):408-18. doi: 10.1039/b618899k. Epub 2007 May 3.
In nature, ribosomally synthesized proteins can contain at least 22 different amino acids: the 20 common amino acids as well as selenocysteine and pyrrolysine. Each of these amino acids is inserted into proteins codon-specifically via an aminoacyl-transfer RNA (aa-tRNA). In most cases, these aa-tRNAs are biosynthesized directly by a set of highly specific and accurate aminoacyl-tRNA synthetases (aaRSs). However, in some cases aaRSs with relaxed or novel substrate specificities cooperate with other enzymes to generate specific canonical and non-canonical aminoacyl-tRNAs.
在自然界中，核糖体合成的蛋白质至少可包含22种不同的氨基酸：20种常见氨基酸以及硒代半胱氨酸和吡咯赖氨酸。这些氨基酸中的每一种都是通过氨酰基转移RNA（aa-tRNA）以密码子特异性的方式插入到蛋白质中的。在大多数情况下，这些aa-tRNA是由一组高度特异性且准确的氨酰基-tRNA合成酶（aaRS）直接生物合成的。然而，在某些情况下，具有宽松或新底物特异性的aaRS会与其他酶协同作用，以生成特定的标准和非标准氨酰基-tRNA。
