Structural basis of cyanobacterial photosystem II Inhibition by the herbicide terbutryn

Broser, M., Glöckner, C., Gabdulkhakov, A., Guskov, A., Buchta, J., Kern, J., Müh, F., Dau, H., Saenger, W. & Zouni, A., 6-May-2011, In : The Journal of Biological Chemistry. 286, 18, p. 15964-15972 9 p.

Research output: Contribution to journalArticleAcademicpeer-review

  • Matthias Broser
  • Carina Glöckner
  • Azat Gabdulkhakov
  • Albert Guskov
  • Joachim Buchta
  • Jan Kern
  • Frank Müh
  • Holger Dau
  • Wolfram Saenger
  • Athina Zouni

Herbicides that target photosystem II (PSII) compete with the native electron acceptor plastoquinone for binding at the Q(B) site in the D1 subunit and thus block the electron transfer from Q(A) to Q(B). Here, we present the first crystal structure of PSII with a bound herbicide at a resolution of 3.2 Å. The crystallized PSII core complexes were isolated from the thermophilic cyanobacterium Thermosynechococcus elongatus. The used herbicide terbutryn is found to bind via at least two hydrogen bonds to the Q(B) site similar to photosynthetic reaction centers in anoxygenic purple bacteria. Herbicide binding to PSII is also discussed regarding the influence on the redox potential of Q(A), which is known to affect photoinhibition. We further identified a second and novel chloride position close to the water-oxidizing complex and in the vicinity of the chloride ion reported earlier (Guskov, A., Kern, J., Gabdulkhakov, A., Broser, M., Zouni, A., and Saenger, W. (2009) Nat. Struct. Mol. Biol. 16, 334-342). This discovery is discussed in the context of proton transfer to the lumen.

Original languageEnglish
Pages (from-to)15964-15972
Number of pages9
JournalThe Journal of Biological Chemistry
Issue number18
Publication statusPublished - 6-May-2011
Externally publishedYes


  • Crystallography, X-Ray, Cyanobacteria, Herbicides, Photosystem II Protein Complex, Protein Structure, Quaternary, Structure-Activity Relationship, Triazines

ID: 12736341