Investigation of dialysis methods for the complete removal of Cl- from photosystem II

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Xiaoming Li (Creator)
The University of North Carolina at Greensboro (UNCG )
Web Site:
Alice Haddy

Abstract: "Photosystem II (PSII), which produces oxygen using light energy, requires Cl- as a cofactor. Cl- appears to be difficult to remove from PSII because there always remains residual activity of 25-40%. We have tested variations of the dialysis method to deplete PSII of Cl- by introducing NO3- or Br- before dialysis. NO3 pretreatment produced a preparation with suppressed activation by NO3-, suggesting that NO3- replaced Cl- at its site of activation. Br- pretreatment produced the preparation with the lowest residual activity and the highest total activity, indicating that it was the best method for Cl- depletion. The electron paramagnetic resonance (EPR) multiline signal from the S2 state was examined in the presence of Cl-, Br- and NO3- in the Cl- depleted PSII pretreated with NO3-. The signal height followed the same trend as oxygen evolution activity with Cl- > Br- > no anion > NO3."--Abstract from author supplied metadata.

Additional Information

Language: English
Date: 2006
Photosystem II (PSII), oxygen, light energy, C1-, depletion, dialysis
Photosynthesis--Molecular aspects
Photosynthetic oxygen evolution

Email this document to