Long-wavelength ultraviolet photoproduction of amino acids on the primitive Earth.

Amino acids are produced under possible primitive Earth conditions by irradiation of gas mixtures with long-wavelength ultraviolet light, representing the most abundant useful energy source for prebiological organic synthesis. Hydrogen sulfide is the initial photon acceptor in this work; superthermal atomic hydrogen photodissociation products appear to initiate reactions leading to amino acid synthesis with an overall quantum yield on the order of 5X10(-5).