Analysis of the nucleotide context of Arabidopsis thaliana mitochondrial mRNA editing sites |
| |
Authors: | Vishnevsky O V Titov I I Konstantinov Yu M |
| |
Institution: | (1) Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia;(2) Pushchino State University, Pushchino, Moscow Region, 142290, Russia |
| |
Abstract: | We have studied the effects of 1 mM solutions of L-amino acids on the X-ray- and heat-induced generation of hydrogen peroxide and hydroxyl radicals in phosphate buffer (5 mM, pH 7.4). Hydrogen peroxide was estimated by enhanced chemiluminescence in the luminol/p-iodophenol/peroxidase system; hydroxyl radicals were detected with a fluorescent probe coumarin-3-carboxylic acid. We demonstrate that amino acids can be grouped into three categories by their effect on X-ray-induced H2O2 production: those that reduce, increase, and have no influence on H2O2 yield. Similar amino acid effects were observed upon heating; however, the composition of respective amino acid groups was different. All amino acids lowered the X-ray-induced hydroxyl radical production, and the most effective were Cys > His > Phe = Met = Trp > > Tyr (in descending order). Hydroxyl radical generation induced by heating was inhibited by Met, His, and Phe; enhanced by Ser; and not affected by Tyr and Pro. Thus, amino acids have different effects on the production of reactive oxygen species by X-rays and heating, and some amino acids appear to be effective natural antioxidants. |
| |
Keywords: | amino acids X-rays heating hydrogen peroxide hydroxyl radicals antioxidants |
本文献已被 SpringerLink 等数据库收录! |
|