Nature CommunicationsEngineering unnatural cells with a 21st amino acid as a living epigenetic sensorYu HuYixian WangLinqi ChengChenhang WangYijie LiuYufei WangYuda ChenShudan YangYiming GuoShiyu JiangKaiqiang YangHan Xiao2025-10-23Full textDOI https://doi.org/10.1038/s41467-025-64448-1