Reaktionen von Wasserstoffperoxyd mit Nucleinsäurebausteinen und s-RNA

Abstract

The reaction rates of excess hydrogen peroxide with nucleic acid constituents were determined. They show that under weak alkaline conditions uridine-3''(2'')-phosphate and thymidine are rapidly attacked with a strong positive pH dependence in contrast to eytidine-3''(2'')-phosphate and guanosin-3''(2'') -phosphate. The latter react only slightly and almost independently of pH, while adenosine-3''(2'') -phosphate shows no loss of extinction. Uracil and its N3-derivatives are degraded, in the pH range of 9-10, to urea- and N-substituted urea, the corresponding urea-N-ribosides or ribosidephosphates, and a peroxide. A kinetically favored degradation of the uracil of s-RNA by excess hydrogen peroxide occurs optimally at 1[degree]C, pH 10. However some side reactions also occur.