Interaction of formaldehyde with nucleic acids and their structural components in the presence of amines. V. Isotopic exchange of hydrogen 3H---1H at the C8 atom of dATP, adenosine, adenine, guanosine, and poly (A)
Volkov, V.S.
Biokhimiia 59(8): 1212-1217
1994
ISSN/ISBN: 0320-9725 PMID: 7819406 Document Number: 425275
It has been shown that the effect on [8-3H]dATP, [8-3H]A and [8-3H]poly(A) of the formaldehyde mixture with the primary aliphatic amine carrying an amino group at the chain terminus (glycine, its methyl and ethyl esters, tripeptide Gly-Gly-Gly, taurine, ethanolamine, methylamine, ethylamine), under conditions close to physiological ones (pH 5.5-9, 40-50 degrees), initiates a fast reaction of isotope H2 exchange: 3H-->1H at the C-8 atom of the adenine residue. Substitution of the primary amine for a secondary one decreases the rate of hydrogen exchange by more than two orders of magnitude. Under the effect of the formaldehyde mixture with Gly or Sar on guanosine or of the HCHO-Sar mixture on adenosine, the hydrogen exchange at the C-8 atom of the both nucleotides proceeds at the same rate. The mechanism of fast hydrogen exchange at the C-8 atom of 9-substituted adenines under conditions of the Mannich reaction via the N6,N7-cycloderivative (III) is discussed.