Table of Contents
Laser Chemistry
Volume 19, Issue 1-4, Pages 201-208
http://dx.doi.org/10.1155/1999/62680

Time-Resolved Resonance Raman Studies of Radicals From 4-Aminoresorcinol as Models for the Active Site Radical Intermediate in Copper Amine Oxidases

1Department of Biological Sciences, University of Salford, Salford M5 4 WT, United Kingdom
2Lasers for Science Facility, Rutherford Appleton Laboratory, Oxon OXll 0QX, United Kingdom

Received 30 April 1997

Copyright © 1999 Hindawi Publishing Corporation. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Radicals formed by one-electron oxidation of 4-aminoresorcinol have been studied as models for the active site free radical intermediate which forms as a stable product during anaerobic incubation of amine oxidases with amine substrates. Pulse radiolysis shows that the radical undergoes ionisations with pKa's of 3.4 and 6.4. Although the two deprotonated forms are difficult to distinguish by absorption spectroscopy, they have clearly different resonance Raman spectra. Comparison with the resonance Raman spectrum of the enzyme intermediate shows it to be the singly deprotonated form of the radical.