Abiotic synthesis of amino acids by x-ray irradiation of simple inorganic gases

1-2 keV x-ray irradiation was carried out using a synchrotron radiation sou rce on simulated primitive earth environment: a gas mixture of carbon monox ide, nitrogen, and water at atmospheric pressure. High-speed liquid chromat ography of the hydrolyzed product solution detected amino acids. The amount of amino acids increased with the total energy absorbed by the gas molecul es, and the antipodal optical isomers were generated in almost equal quanti ties. These imply that the precursors for amino acids were produced through x-ray-induced photolysis of inorganic molecules followed by recombination and polymerization into bio-organic compounds. These results suggest that p rebiotic formation of amino acids is possible in primitive earth atmosphere by x ray as well as cosmic ray. (C) 1999 American Institute of Physics. [S 0003-6951(99)00906-7].