Die oxydation von adenosinderivaten zu N1-oxyden und der einbau von ADP-N1-oxyd in poly-a durch bakterien-rohextrakte

Oxidation of DNA bases, deoxyribonucleosides and homopolymers by peroxyl radicals

“…Other known products of purine radical oxidations, specifically 2 and 7 ( Figure 1A) and 9 ( Figure 1B), were not detected in any of the ROOd oxidations. Adenine 1-N-oxide (3, Figure 1A) and guanine-3-N-oxide (11, Figure 1B) are established as the major N-oxide regioisomers formed in the oxidations of A and G respectively by H # O # \acetic acid [43], magnesium monoperoxyphthalate hexahydrate [44] and m-chloroperoxybenzoic acid [45,46] ; neither compound was detected in any incubations. (N-Oxide isomers 4, 5 and 10 would have exhibited similar mass spectra to the established isomer.)…”

Cosubstrate and allosteric modifier activities of structural analogs of NAD and ADP for NAD-specific isocitrate dehydrogenase from bovine heart

“…Thus, 8-bromo-ADP, l-A'-oxide-ADP, and 2-OH-ADP (2hydroxy-6-aminopurine nucleoside diphosphate) were not positive effectors (Table III). 1-A-Oxide-ADP has been reported by a number of investigators to replace ADP in certain phosphotransferase reactions (Cramer et al, 1963;Mantsch et al, 1975); however, it was inactive as a modifier for bovine liver glutamate dehydrogenase (Mantsch et al, 1975) and it was neither an activator nor inhibitor for isocitrate dehydrogenase (Table III). On the other hand, 2-OH-ADP (and 2-OH-ATP) has been reported by Mantsch et al (1975) to be a potent inhibitor of glutamate dehydrogenase.…”

Purine N-Oxides. XII. Photochemical Changes Induced by Ultraviolet Radiation*

“…Because of the ease of oxidation of adenine nucleotides to their l-AI-oxides by neutral hydrogen peroxide (Stevens et al, 1959; Cramer and Randerath, 1958;Cramer et al, 1963) and of the secondary production of peroxides by ionizing radiation (Scholes and Weiss, 1952), we first attempted the production of an adenine -oxide derivative by the action of ultraviolet light or X irradiation without success, for reasons now obvious. Subsequently we found that 50% of adenine oxide in an unbuffered aqueous solution may be altered in 45 minutes by an intensity of ultraviolet light which does not measurably alter adenine in 4 days; it is altered with the remarkably high quantum efficiency of 0.1 (Levin et al, 1964).…”