Kinetic Study of the Formation of the Radiolysis Products of Cytosine Resulting from the Deamination Pathway

After gamma irradiation of cytosine in aerated aqueous solution, yields of chemical radiation products belonging to the deamination pathway were measured. Primary stable radiolysis products, such as 5,6-dihydroxy-5,6-dihydro-uracil cis and trans forms, were present with G values lower than those obtained in the radiolysis of uracil irradiated under the same conditions. Cytosine had the same radiosensitivity as uracil (G= -2.49).