The 7th Symposium of the Biophysical Society of Taiwan
“Recent Advances in Biophysics” (May 23 – 26, 2001)
Hemoglobin-mediated nonenzymatic reduction of 8-nitroguanine, 8-nitroxanthine, and 3-nitrotyrosine by biological antioxidants
Yuan-Mao Chen (陳源茂) and Hauh-Jyun Candy Chen* (陳皓君)
Department of Chemistry, National Chung Cheng University, 160 San-Hsing, Ming-Hsiung, Chia-Yi 62142, TAIWAN.
國立中正大學化學系暨化學研究所, 621 嘉義縣民雄鄉三興村160號
Reactive nitrogen species (RNS), such as peroxynitrite and nitryl chloride, have been shown to give rise to the nitrated DNA and protein adducts, 8-nitroguanine (8NG), 8-nitroxanthine (8NX), and 3-nitrotyrosine (3NT). DNA damages caused by these reactive nitrogen species may contribute to the multistage carcinogenesis process associated with chronic infections and inflammation. These nitrated DNA adducts are not stable in DNA and lead to formation of apurinic sites. Modification of proteins forming 3NT is implicated in alteration of protein functions by RNS. We herein report that reduction of 8NG, 8NX, and 3NT to their corresponding amino analogues by antioxidants is mediated by hemoglobin under physiological conditions. Besides dithiothreitol, biological antioxidants including lipoic acid, quercetin, and ascorbate, reduced glutathione, and caffeic acid gave the amino products in various extents, whereas b-nicotinamide adenine dinucleotide is not effective. These results identify certain biological antioxidants effective in decreasing the levels of nitrated DNA and protein adducts. However, whether the biological consequences of forming the amino analogues as secondary products being less detrimental than the parent nitrated adducts requires further investigation.
您的論文是屬於下列那個學門? ___g__ a. Cell biophysics; b. Ion Channels; c. Computer simulation; d. Membrane biophysics; e. New methods; f. NMR; g. Nucleic acids; h. Photobiophysics;
i. Protein engineering; j. Protein folding; k. Theoretical biophysics; l. X-ray crystallography; m. Others
Address:_ 621 嘉義縣民雄鄉三興村160號 國立中正大學化學系暨化學研究所_________
P.I.’s Name:____陳皓君______Signature:____ 陳皓君_____________ Date:_05/02/01__
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Poster board size: 146cm x 86cm
Deadline: April 15, 1999 (電子論文摘要請送biophys@gate.sinica.edu.tw，截止日期為五月四日)
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