Activated carcinogen-nucleotide

Metabolically activated carcinogens covalently bind in vitro to mouse epidermal DNA similar to in vivo (Nakayama et al. 1984). In vitro DNA repair processes operate to fix single-strand DNA. There is base excision, nucleotide excision, mismatch repair as well as double-strand repair (for double-strand breaks), and UV and... 

In addition to influencing hydrocarbon metabolite-DNA reactions, the physical binding properties of hydrocarbon metabolites covalently bound to DNA may also be important to carcinogenic activity. The covalent binding of ultimate carcinogens derived from BP and DMBA to DNA produces adducts with tt binding properties similar to those of naturally occurring nucleotides. These adducts... 

Nitration opens up another pathway to metabolic activation. Nitro-PAHs are wide-spread environmental pollutants that are mutagenic and carcinogenic. Metabolism of nitro-PAHs could occur via nitro-activation (reduction to hydroxylamine, eventually leading to nitrenes that can bind to nucleotides) and/or by ring oxidation and formation of DEs. ... 

Gruetter, C. A., Barry, B. K., McNamara, D. B., Gruetter, D. Y., Kadowitz, P. J., and Ignarro, L. J. (1979). Relaxation of bovine coronary artery and activation of coronary arterial guanylate cyclase by nitric oxide, nitroprusside and a carcinogenic nitrosoam-ine. ]. Cyclic Nucleotide Protein Phosphorylation Res. 5, 211-224. 

In this section we should like to point out the possibility of two different kinds of solitons (non-linear quasi particles) in a nucleotide base stack. They quite probably play an important role in long-range effects of chemical carcinogens and direct hits of ionizing radiations along a DNA double helix. In this way they may play an important role in the activation of oncogenes or in the inactivation of antioncogenes. 

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