Photosystem I pp 193-204 | Cite as

Mutagenesis of Ligands to the Cofactors in Photosystem I

  • Andrew N. Webber
  • Velupillaimani M. Ramesh
Part of the Advances in Photosynthesis and Respiration book series (AIPH, volume 24)


The electron transfer chain of Photosystem I (PS I) is made up of six chlorophylls (P700, A, and A0), two quinones (A1), and three iron–sulfur centers (FXX, FA, and FB). The chlorophylls and quinones formtwo potential pathways for electron transfer from P700 to FX. The electron transfer chain chlorophylls are also excitonically coupled as indicated by the spectrally broad transient bleaching observed between 660 and 700 nm upon initial excitation. This article reviews how specific mutagenesis of the ligands of each cofactor is being used to address some of the outstanding questions raised by the structural model of Photosystem I.


Electron Transfer Electron Paramagnetic Resonance Axial Ligand Primary Charge Separation Sulfur Center 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer 2006

Authors and Affiliations

  • Andrew N. Webber
    • 1
  • Velupillaimani M. Ramesh
    • 1
  1. 1.School of Life Sciences and Center for Early Events in PhotosynthesisArizona State UniversityTempeUSA

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