Vanadyl-Induced Fenton-Like Reaction in RNA. An ESR and Spin Trapping Study
Abstract
The purpose of this work is to study, using ESR and spin trapping, vanadyl-induced Fenton-like reactions in RNA. Spin trapping is a technique by which a short-lived free radical is reacted with a spin trap, usually a nitrone or nitroso compound, to give a longer-lived nitroxide spin adduct which can be identified by ESR. The oxycation of vanadium(IV), vanadyl(VO2+), has proven to be an effective spin probe in biological systems. Vanadyl has a single unpaired electron in its lowest nondegenerate vanadium dxy orbital. In a magnetic field, this electron interacts with the 51V nucleus (99.7% abundant) which has a nuclear spin, I = 7/2, generating an isotropic ESR spectrum at room temperature consisting of 8 sharp lines. However, when VO2+ is bound to a membrane component or to a slowly tumbling large molecule (protein, nucleic acid) in solution, it yields an anisotropic ESR spectrum of immobilized vanadyl in a polycrystalline state or frozen solution. The versatility of vanadyl as spin probe and its capacity to yield important information with regard to metal properties in biological systems, is due mainly to this susceptibility of the vanadyl ESR spectrum to the motion of the cation in solution. Keywords: Vanadium; Vanadyl; Hydrogen peroxide; Hydroxyl radical; Electron spin resonance; Spin trapping. Reprints.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1990
- Accession Number
- ADA224101
Entities
People
- Alasdair J. Carmichael
Organizations
- Armed Forces Radiobiology Research Institute