title: The direct genetic encoding of pyrrolysine.
abstract: Pyrrolysine is an amino acid encoded by the amber codon in genes required for methylamine utilization by members of the Methanosarcinaceae. Pyrrolysine and selenocysteine share the distinction of being the only two non-canonical amino acids that have entered natural genetic codes. Recent experiments have shown that encoding of pyrrolysine, unlike that of selenocysteine, also shares an important trait of the original set of twenty amino acids. UAG is translated as pyrrolysine with the participation of a dedicated aminoacyl-tRNA synthetase. Expression of the genes encoding the pyrrolysyl-tRNA synthetase and its cognate tRNA is sufficient to add pyrrolysine to the genetic code of a recombinant organism. Thus, the recruitment of pyrrolysine into the genetic code involved evolution of the first non-canonical aminoacyl-tRNA synthetase and cognate tRNA to be described from nature.
authors.affiliation: Department of Microbiology, OSU Biochemistry Program, Ohio State University, Columbus, OH 43210, USA. krzycki.1@osu.edu
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Krzycki
mesh_terms: D000595:Amino Acid Sequence; D000604:Amino Acyl-tRNA Synthetases / Q000235:genetics / Q000378:metabolism; D019843:Archaeal Proteins / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D003062:Codon / Q000235:genetics*; D005815:Genetic Code; D008239:Lysine / Q000031:analogs & derivatives* / Q000235:genetics / Q000378:metabolism; D017019:Methanosarcinaceae / Q000235:genetics* / Q000378:metabolism; D008744:Methylamines / Q000378:metabolism; D008969:Molecular Sequence Data; D012345:RNA, Transfer, Amino Acid-Specific / Q000235:genetics / Q000378:metabolism
chemical_list: D019843:Archaeal Proteins; D003062:Codon; D008744:Methylamines; D012345:RNA, Transfer, Amino Acid-Specific; C027451:methylamine; D000604:Amino Acyl-tRNA Synthetases; C456839:pyrrolysine; D008239:Lysine