Damage to the oxygen-evolving complex by superoxide anion, hydrogen peroxide, and hydroxyl radical in photoinhibition of photosystem II

Photosynth Res. 2006 Oct;90(1):67-78. doi: 10.1007/s11120-006-9111-7. Epub 2006 Nov 28.

Abstract

Under strong illumination of a photosystem II (PSII) membrane, endogenous superoxide anion, hydrogen peroxide, and hydroxyl radical were successively produced. These compounds then cooperatively resulted in a release of manganese from the oxygen-evolving complex (OEC) and an inhibition of oxygen evolution activity. The OEC inactivation was initiated by an acceptor-side generated superoxide anion, and hydrogen peroxide was most probably responsible for the transportation of reactive oxygen species (ROS) across the PSII membrane from the acceptor-side to the donor-side. Besides ROS being generated in the acceptor-side induced manganese loss; there may also be a ROS-independent manganese loss in the OEC of PSII. Both superoxide anion and hydroxyl radical located inside the PSII membrane were directly identified by a spin trapping-electron spin resonance (ESR) method in combination with a lipophilic spin trap, 5-(diethoxyphosphoryl)-5-phenethyl-1-pyrroline N-oxide (DEPPEPO). The endogenous hydrogen peroxide production was examined by oxidation of thiobenzamide.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Electron Spin Resonance Spectroscopy
  • Hydrogen Peroxide / metabolism
  • Hydrogen Peroxide / pharmacology*
  • Hydroxyl Radical / pharmacology*
  • Kinetics
  • Light
  • Oxygen / metabolism*
  • Photosystem II Protein Complex / drug effects
  • Photosystem II Protein Complex / physiology*
  • Spinacia oleracea / metabolism*
  • Spinacia oleracea / radiation effects
  • Superoxides / pharmacology*

Substances

  • Photosystem II Protein Complex
  • Superoxides
  • Hydroxyl Radical
  • Hydrogen Peroxide
  • Oxygen