Evaluation of the role hydroxyl radicals and iron play in hydrogen peroxide killing of Xanthomonas campestris pv. phaseoli

摘要

Hydroxyl radical, a product of H2O2 metabolism in the Fenton reaction, is a major reactive oxygen species involved in H2O2 killing of Xanthomonas campestris pv. phaseoii (Xp). Compounds which absorbed hydroxyl radicals protected Xanthomonas from H2O2 killing, but not from killing by a superoxide generator or an organic peroxide. Addition of iron potentiated H2O2 killing. On the other hand, pre-treatment of Xp with an iron chelator showed no protective effects and H2O2 killing was actually enhanced. Unexpectedly, resuspension of Xp in either water or phosphate buffer induced high-level resistance to H2O2 killing. The unknown protection mechanism was independent of new protein synthesis. (C) 1998 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved. [References: 16]