AUTHOR=Di Salvo Martino L. , Fesko Kateryna , Phillips Robert S. , Contestabile Roberto TITLE=Editorial: PLP-Dependent Enzymes: Extraordinary Versatile Catalysts and Ideal Biotechnological Tools for the Production of Unnatural Amino Acids and Related Compounds JOURNAL=Frontiers in Bioengineering and Biotechnology VOLUME=8 YEAR=2020 URL=https://www.frontiersin.org/journals/bioengineering-and-biotechnology/articles/10.3389/fbioe.2020.00052 DOI=10.3389/fbioe.2020.00052 ISSN=2296-4185