Catalysis of oxidation of nitrogen compounds by flavin coenzymes in the presence of light.

When it was discovered in this laboratory that sarcosine and dimethylglycine are oxidized to formaldehyde by riboflavin phosphate and riboflavin in the absence of protein,1 this observation was pursued, not only because of our interest in the enzymatic oxidation of these substrates, but also because of its implications regarding the origin of biochemical reactions. Subsequent studies to be described below, have demonstrated that these nonenzymatic reactions are photochemical and occur only when the nitrogen compounds, plus catalytic amounts of the riboflavin phosphate are exposed to light. The mechanism of this photooxidation has been investigated by employing as substrates sarcosine and dimethylglycine labeled with Cl4 and also homologous derivatives of these amino acids.