title: Inhibition of photosystem II of spinach by the respiration inhibitors piericidin A and thenoyltrifluoroacetone.
abstract: The effects of several respiration inhibitors on photosystem II (PS II) were investigated. Among the agents tested, piericidin A and thenoyltrifluoroacetone (TTFA) inhibited the photosynthetic electron transport of spinach as measured from chlorophyll (Chl) fluorescence parameters (Fm'-F)/Fm' and Fv/Fm. Using specific donors and acceptors of electrons, we identified the sites of inhibition in and around the PS II complex; the site of inhibition by TTFA was between QA, primary quinone acceptor in PS II, and QB, secondary quinone acceptor, in the acceptor side of P680, the reaction center Chl of PS II, while inhibition by piericidin A of the acceptor side was downstream of Q(B), out of the PS II complex. Both agents also inhibited the donor side of P680, probably between tyrosine-161 of the reaction center protein of PS II and P680.
authors.affiliation: Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Sakyo, Japan.
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Ikezawa
authors.forename: Kentaro
authors.initials: K
authors.lastname: Ifuku
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Endo
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Sato
mesh_terms: D019069:Cell Respiration / Q000187:drug effects; D002734:Chlorophyll / Q000378:metabolism; D004579:Electron Transport / Q000187:drug effects; D005453:Fluorescence; D045342:Light-Harvesting Protein Complexes; D010788:Photosynthesis / Q000187:drug effects*; D045322:Photosynthetic Reaction Center Complex Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D045332:Photosystem II Protein Complex; D011725:Pyridines / Q000494:pharmacology*; D018724:Spinacia oleracea / Q000187:drug effects* / Q000378:metabolism*; D013804:Thenoyltrifluoroacetone / Q000494:pharmacology*; D020524:Thylakoids / Q000187:drug effects / Q000378:metabolism
chemical_list: D045342:Light-Harvesting Protein Complexes; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D011725:Pyridines; D002734:Chlorophyll; D013804:Thenoyltrifluoroacetone; C100213:piericidin A