Nonnatural amino acids with photofunctional groups were incorporated site-specifically into a polypeptide by using in vitro protein synthesizing system. The nonnatural amino acids were attached to tRNACCU through chemical misacylation method, and added to the in vitro system with a mRNA containing a single AGG codon. l-p-Phenylazophenylalanine, l-2-anthrylalanine, l-1-naphthylalanine, l-2-naphthylalanine and l-p-biphenylalanine were successfully incorporated into a polypeptide, but l-1-pyrenylalanine was not. The polypeptides containing the nonnatural amino acids showed photofunctionalities.
