Gamma-irradiation studies with synthetic poly-L-serine in the megarad dose range

Gamma irradiation of poly-L-serine was carried out in dilute aqueous solutions (50 micrograms/ml) in the dose range 0.44-2.64 megarad. Damage to the peptide bond studied through u.v. spectral absorption and gel filtration on a Sephadex G50 column and damage to the serine side groups through t.l.c. and amino acid analysis of the hydrolyzed samples indicate higher radiosensitivity of the side groups as compared to that of the peptide bond even in the megarad range. Early damage to the serine side groups seems to result in the formation of glycine.