[Interaction of DNA and hydrogen peroxide. A method of localizing pyrimidine bases in DNA]

Incomplete modification with hydrogen peroxide of the DNA fragments labeled at one terminus is shown to be useful for localisation of C and T residues along the polynucleotide chain. The fragments can be split at modified residues with piperidine after hydrogen peroxide treatment. The rate of the reaction of the single-stranded fragments is extremely fast, much higher than that of the double-stranded DNA. Splitting of the DNA takes place at C if pH 7,4, and at T at pH 9,6. The modification can be used to investigate the DNA structure and function.