title: The path of lysine to pyrrolysine.
abstract: Pyrrolysine is the 22nd genetically encoded amino acid. For many years, its biosynthesis has been primarily a matter for conjecture. Recently, a pathway for the synthesis of pyrrolysine from two molecules of lysine was outlined in which a radical SAM enzyme acts as a lysine mutase to generate a methylated ornithine from lysine, which is then ligated to form an amide with the ɛ-amine of a second lysine. Oxidation of the isopeptide gives rise to pyrrolysine. Mechanisms have been proposed for both the mutase and the ligase, and structures now exist for each, setting the stage for a more detailed understanding of how pyrrolysine is synthesized and functions in bacteria and archaea.
authors.affiliation: Department of Microbiology, 484 West 12th Avenue, Columbus, OH 43210, United States. Krzycki.1@osu.edu
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Krzycki
mesh_terms: D019751:Intramolecular Transferases / Q000378:metabolism; D008025:Ligases / Q000378:metabolism; D008239:Lysine / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000378:metabolism*; D008745:Methylation; D010084:Oxidation-Reduction
chemical_list: D019751:Intramolecular Transferases; D008025:Ligases; C456839:pyrrolysine; D008239:Lysine