AUTHOR=Bag Subhendu Sekhar , Saraogi Ishu , Guo Jiantao TITLE=Editorial: Expansion of the Genetic Code: Unnatural Amino Acids and their Applications JOURNAL=Frontiers in Chemistry VOLUME=10 YEAR=2022 URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2022.958433 DOI=10.3389/fchem.2022.958433 ISSN=2296-2646