The activity and function of proteins can be improved by incorporation of non-canonical amino acids (ncAAs). To avoid the tedious synthesis of a large number of chiral phenylalanine derivatives, we synthesized the corresponding phenylpyruvic acid precursors. Escherichia coli strain DH10B and strain C321.ΔA.expΔPBAD were selected as hosts for phenylpyruvic acid bioconversion and genetic code expansion using the MmPylRS/^pyltRNA_CUA system. The concentrations of keto acids, PLP and amino donors were optimized in the process. Eight keto acids that can be biotransformed and their coupled genetic code expansions were identified. Finally, the genetic encoded ncAAs were tested for incorporation into fluorescent proteins with keto acids.

中文翻译：

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通过其 α-酮酸前体对苯丙氨酸衍生物进行方便的遗传编码

蛋白质的活性和功能可以通过加入非经典氨基酸 (ncAAs) 来提高。为了避免大量手性苯丙氨酸衍生物的繁琐合成，我们合成了相应的苯丙酮酸前体。使用Mm PylRS/ ^pyl tRNA _CUA系统选择大肠杆菌菌株 DH10B 和菌株 C321.ΔA.expΔPBAD 作为苯丙酮酸生物转化和遗传密码扩增的^宿主。在该过程中优化了酮酸、PLP 和氨基供体的浓度。确定了八种可以生物转化的酮酸及其耦合的遗传密码扩展。最后，测试了遗传编码的 ncAAs 与酮酸结合到荧光蛋白中的情况。