TY - JOUR
T1 - Identification of the site of iodide photooxidation in the photosystem II reaction center complex
AU - Takahashi, Yuichiro
AU - Takahashi, Masa aki
AU - Satoh, Kimiyuki
N1 - Funding Information:
This work was supportedi n part by grantsf rom Grant-in-Aid (61740390t)o Y.T. and those for SpecialP roject Researcho n FundamentaAl spects of Photosynthesis( 59127027)E, nergy Research (58045106a)n d Co-operativeR esearcho n Oxygen Evolving Systemo f Photosynthesis( 58340057t)o K.S. from the Ministry of Education, Sciencea nd Culture of JapaneseG overnment.
PY - 1986/11/24
Y1 - 1986/11/24
N2 - The highly purified PS II reaction center complex with 47, 43, 32, 30 and 9 kDa (and 4.5 kDa) polypeptides was subjected to iodo-labeling to identify the polypeptide(s) participating on the donor side of the photosystem. The 32 kDa component (D2) and the aggregate(s) of about 60 kDa were exclusively labeled in the dark, suggesting the presence of a dark-stable oxidizing component on this polypeptide. Illumination of the complex in the presence of 2,6-dichlorophenolindophenol and iodide resulted in the preferential iodination of the 30 kDa component (D1) and the aggregate(s), but not the 47 kDa polypeptide. This iodo-labeling was completely inhibited by the addition of an electron donor, 1,5-diphenylcarbazide. From these results, it is concluded that the site of photooxidation of iodide, and presumably the site of Z binding, is located on or near the herbicide-binding polypeptide, D1, in the PS II reaction center complex.
AB - The highly purified PS II reaction center complex with 47, 43, 32, 30 and 9 kDa (and 4.5 kDa) polypeptides was subjected to iodo-labeling to identify the polypeptide(s) participating on the donor side of the photosystem. The 32 kDa component (D2) and the aggregate(s) of about 60 kDa were exclusively labeled in the dark, suggesting the presence of a dark-stable oxidizing component on this polypeptide. Illumination of the complex in the presence of 2,6-dichlorophenolindophenol and iodide resulted in the preferential iodination of the 30 kDa component (D1) and the aggregate(s), but not the 47 kDa polypeptide. This iodo-labeling was completely inhibited by the addition of an electron donor, 1,5-diphenylcarbazide. From these results, it is concluded that the site of photooxidation of iodide, and presumably the site of Z binding, is located on or near the herbicide-binding polypeptide, D1, in the PS II reaction center complex.
KW - Photosystem II Reaction center Iodo-labeling Secondary electron donor Herbicide-binding protein
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U2 - 10.1016/0014-5793(86)81047-X
DO - 10.1016/0014-5793(86)81047-X
M3 - Article
AN - SCOPUS:0003198870
SN - 0014-5793
VL - 208
SP - 347
EP - 351
JO - FEBS Letters
JF - FEBS Letters
IS - 2
ER -