title: Mass spectroscopic approach to amino acids formation processes by UV irradiation to simple organic molecules in aqueous solution.
abstract: We have studied amino acid formation by UV (193 nm) irradiation to organic molecules (amines, alcohols and amides) in aqueous solution. Among several types of detected amino acids, small aliphatic amino acids (Gly and alpha-, beta-Ala and alpha-, beta-, gamma-ABA) were quantitatively identified. Among these small aliphatic amino acids, certain amino acids were formed in its free form, even before hydrolysis, contrary to the results of UV irradiation to a gas mixture of CO, NH3, and H2O, where amino acids were hardly detected before hydrolysis. The species distribution of identified amino acids showed a dependence on the starting organic molecules, and also on the presence of ammonia. The formation processes of the identified small aliphatic amino acids were investigated with the aid of electrospray ionization (ESI) MS and MS/MS measurements of photoproducts. Possible formation processes of these amino acid precursors from each starting molecules are proposed. By identifying the amino acid precursor, which has a chiral carbon atom, a new possibility is suggested for asymmetric photosynthesis of amino acid from achiral organic molecules.
authors.affiliation: Department of Physical Science, Graduate School of Science, Hiroshima University, Higashihiroshima, Japan. mmv25001@se.ritsumei.ac.jp
authors.forename: Masaki
authors.initials: M
authors.lastname: Morita
authors.forename: Yoshie
authors.initials: Y
authors.lastname: Harada
authors.forename: Kunihiro
authors.initials: K
authors.lastname: Iseki
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Izumi
authors.forename: Atsunari
authors.initials: A
authors.lastname: Hiraya
mesh_terms: D000596:Amino Acids / Q000032:analysis / Q000138:chemical synthesis*; D019418:Evolution, Chemical; D008968:Molecular Conformation / Q000528:radiation effects; D009930:Organic Chemicals / Q000737:chemistry / Q000528:radiation effects*; D012996:Solutions / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D014466:Ultraviolet Rays; D014867:Water / Q000737:chemistry*
chemical_list: D000596:Amino Acids; D009930:Organic Chemicals; D012996:Solutions; D014867:Water