Attenuation of guanine oxidation via DNA-mediated electron transfer in a crowded environment using small cosolutes
Makiko Tanaka1, Takayuki Matsumoto, Hiroki Iida
1Department of Engineering Science, Graduate School of Informatics and Engineering, The University of Electro-Communications, 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585, Japan. makiko.tanaka@uec.ac.jp.
Abstract:
Guanine oxidation induced by photoirradiation on a pyrene-modified oligonucleotide was investigated under molecular crowding using small cosolutes such as glycerol. The efficiency of guanine photooxidation was suppressed in accordance with the increase in the concentration of glycerol. The results of photooxidation experiments using fully matched and mismatched DNA showed that guanine decomposition was mainly caused by DNA-mediated electron transfer (ET) in glycerol mixed solutions, as well as in diluted aqueous buffer solutions. Multiple factors can contribute to the suppression of guanine oxidation in crowded environments. However, our experimental results indicated that the attenuation of the DNA-mediated ET process suppressed guanine oxidation. On the other hand, experiments using ethylene glycol showed that the guanine decomposition efficiency varies depending on the surrounding solvent. These results suggested that changes in the characteristics of the surrounding medium affect the DNA fluctuation, dominating DNA-mediated ET.
Related Concept Videos
Ionic Bonding and Electron Transfer
Transcription Attenuation in Prokaryotes
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
Oxidation Numbers
Oxidation-Reduction Reactions
Pyruvate Oxidation
First, the enzyme pyruvate dehydrogenase removes the carboxyl group from pyruvate and releases it as carbon dioxide. The stripped molecule is then oxidized and releases electrons, which are then picked up by NAD+...
Electron Carriers
Over the many stages of cellular respiration, glucose breaks down into carbon dioxide and water. Electron carriers pick up electrons lost by glucose in these reactions, temporarily storing and releasing them into the electron...


