Radiation-Activated Nuclease Activity of o,o′-Diphenyleneiodonium Cations (DPI): A Reductively Initiated Chain Reaction Involving the C1′ Chemistry
Document Type
Article
Publication Date
4-1-2003
Description
o,o′-Diphenyleneiodonium cations (DPI) convert relatively harmless radiation-produced electrons into efficient DNA cleaving agents. The cleavage products are unaltered DNA bases, 5-methylenefuranone (5-MF), and a complete set of 3′ and 5′-phosphorylated DNA fragments. The production of alkali-labile sites is a minor factor in the process. Based on the production of 5-MF, it is concluded that DNA cleavage by DPI cations involves (but may not be limited to) the C1′ chemistry. The loss of 3-aminoDPI (ADPI) cations bound to highly polymerized calf thymus DNA appears to be due to a short-chain reaction with an apparent length of up to 2.1 ADPI cations consumed for each radiation-produced electron. The suggested chain reaction mechanism includes the one-electron oxidation of DNA radicals (including the C1′ sugar radical) by ADPI cations bound to the same duplex. The yields of DNA loss in complexes formed by ADPI with short synthetic duplexes indicate that there is more than a 60% probability of DNA damage after one-electron reduction of ADPI.
Citation Information
Razskazovskiy, Yuriy. 2003. Radiation-Activated Nuclease Activity of o,o′-Diphenyleneiodonium Cations (DPI): A Reductively Initiated Chain Reaction Involving the C1′ Chemistry. Radiation Research. Vol.159(4). 543-549. https://doi.org/10.1667/0033-7587(2003)159[0543:RANAOO]2.0.CO;2 PMID: 12643799 ISSN: 0033-7587