Jump to main content
Jump to site search

Issue 106, 2015
Previous Article Next Article

Effects of an acid–alkaline environment on the reactivity of 5-carboxycytosine with hydroxyl radicals

Author affiliations

Abstract

A hydroxyl radical (˙OH) is produced in biological systems by external or endogenous agents. It can damage DNA/RNA by attacking pyrimidine nucleobases through an addition reaction and H-atom abstraction. However, the correlation study for the new cytosine derived DNA modification (5-carboxycytosine, 5-caCyt) remains scarcely existent. Here three distinct groups of mechanisms for 5-caCyt with ˙OH by the CBS-QB3 approach have firstly been explored: the direct reaction (paths R1–R6), acidic (paths R1′–R3′, R5′, R6′), and alkaline (paths R1′′–R5′′)-induced processes. It indicates that the addition of ˙OH to the C5[double bond, length as m-dash]C6 double bond of 5-caCyt is more favourable in neutral, acidic and alkaline conditions, and the ΔGs≠ value of the C5 channel is a little higher than that of the C6 route, which agrees with the tendencies observed experimentally. Moreover, the H5 abstraction in alkaline media might be competitive with the addition reactions, having a ΔGs≠ value of 32.55 kJ mol−1, which is only 17–20 kJ mol−1 more energetic than for the addition reactions. In addition, the ΔGs≠ values of the ˙OH reactions are slightly lower for the neutral or deprotonated systems than for the N3-protonated 5-caCyt, implying that the reaction trends are a little enhanced. Our results give a possible new insight on 5-caCyt in the presence of ˙OH for experimental scientists.

Graphical abstract: Effects of an acid–alkaline environment on the reactivity of 5-carboxycytosine with hydroxyl radicals

Back to tab navigation

Supplementary files

Publication details

The article was received on 27 Aug 2015, accepted on 24 Sep 2015 and first published on 24 Sep 2015


Article type: Paper
DOI: 10.1039/C5RA17393K
Author version
available:
Download author version (PDF)
Citation: RSC Adv., 2015,5, 87364-87376
  •   Request permissions

    Effects of an acid–alkaline environment on the reactivity of 5-carboxycytosine with hydroxyl radicals

    L. Jin, C. Zhao, T. Zhang, Z. Wang, S. Min, W. Wang and Y. Wei, RSC Adv., 2015, 5, 87364
    DOI: 10.1039/C5RA17393K

Search articles by author

Spotlight

Advertisements