Non-cyclic photophosphorylation by spinach grana treated with O.8 M Tris buffer

スポンサーリンク

概要

• 論文の詳細を見る

• 1. Photophosphorylation was measured with spinach grana sambles washed by 0.8 M Tris buffer at pH 8.0, which no longer catalyzed the ferricyanide and NADP HILL reactions with water as the electron donor. The photophosphorylation with the reaction mixture containing 2×10^<-4> M 2,6-dichlorophenol indophenol (DCPI) plus above 2×10^<-3> M ascorbate as the electron donor system instead of water under anaerobic conditions was, in the most part, dependent on the addition of both PPNR (a non-heme iron protein requisite for photosynthetic pyridine nucleotide reduction;spinach ferredoxin) and NADP as the electron acceptor system. However, when ascorbate concentration only was lowered to 2×10^<-4> M, the entire photophosphorylation proceeded, even in the absence of the electron acceptor system. 2. When the NADP added in the reaction mixture had been reduced by glucose-6-phosphate and glucose-6-phosphate dehydrogenase before illumination, the photophosphorylation with 2×10^<-4> M DCPI plus 6.7×10^<-3>M ascorbate decreased to about the same rate as that obtained without NADP. 3. The time course for photophosphorylation in the presence of NADP was consistent with the time course for the photoreduction of NADP: On the complete reduction of NADP, the photophosphorylation stopped. 4. In the presence of 6×10^<-7> M dichlorophenyl-1,1-dimethylurea or 3×10^<-4> M o-phenanthroline, non-cyclic photophosphorylation with 2×10^<-4> M DCPI plus 6.7×10^<-3> M ascorbate as the electron donor system decreased to about half that of the control, and the remaining activities were hardly affected even at higher concentrations of both inhibitors. The P/2e^- ratios of non-cyclic photophosphorylation in the absence and presence of o-phenanthroline were 0.74 and 0.48, respectively.

• 日本植物生理学会の論文

著者

• Horio Takekazu

  Division Of Enzymology Institute For Protein Research Osaka University

• YAMASHITA TAKASHI

  Division of Enzymology, Institute for Protein Research,Osaka University

• Yamashita Takashi

  Division Of Enzymology Institute For Protein Research Osaka University

関連論文

• Evidence from Crosslinking for Nearest-Neighbor Relationships among the Three Extrinsic Proteins of Spinach Photosystem II Complexes that are Associated with Oxygen Evolution
• Non-cyclic photophosphorylation by spinach grana treated with O.8 M Tris buffer

スポンサーリンク