The cover feature picture shows the identification of mutations in pyrrolysyl‐tRNA synthetase that improve the genetic incorporation of noncanonical amino acids at amber codons. These mutations were identified through alternating random mutagenesis of the N‐terminal domain of pyrrolysyl‐tRNA synthetase and screening. Their general effects on improving the genetic incorporation of noncanonical amino acids were demonstrated on three noncanonical amino acids, as shown in the cover feature picture. The picture was prepared by Sunshine Leeuwon. More information can be found in the communication by W. R. Liu et al. on page 26 in Issue 1, 2018 (DOI: 10.1002/cbic.201700268).

中文翻译：

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封面：不断发展的Pyrrolysyl-tRNA合成酶的N末端域，以改善非典型氨基酸的掺入（ChemBioChem 1/2018）

封面特征图片显示了对吡咯基-tRNA合成酶中突变的鉴定，该突变可改善琥珀色密码子上非经典氨基酸的遗传掺入。这些突变是通过对吡咯烷基tRNA合成酶的N端结构域进行随机随机诱变和筛选而鉴定的。如封面特征图所示，在三种非经典氨基酸上证明了它们对改善非经典氨基酸的遗传掺入的一般作用。图片是由阳光丽苑（Sunshine Leeuwon）准备的。在W. R. Liu等人的来文中可以找到更多信息。关于在第1期，2018第26页（：10.1002 / cbic.201700268 DOI）。