Department of Cell and Molecular Biology, Division of Biological Sciences, The University of Michigan, Ann Arbor, Michigan 48109.
Plant Physiol. 1977 Oct;60(4):592-6. doi: 10.1104/pp.60.4.592.
Incubation of KCN-Hg-NH(2)OH-inhibited spinach (Spinacia oleracea L.) chloroplasts with p-phenylenediamine for 10 minutes in the dark prior to illumination produced rates of photosystem II cyclic photophosphorylation up to 2-fold greater than the rates obtained without incubation. Partial oxidation of p-phenylenediaine with ferricyanide produced a similar stimulation of ATP synthesis; addition of dithiothreitol suppressed the stimulation observed with incubation. Addition of ferricyanide in amounts sufficient to oxidize completely p-phenylenediamine failed to inhibit completely photosystem II cyclic activity. This is due at least in part to the fact that the ferrocyanide produced by oxidation of p-phenylenediamine is itself a catalyst of photosystem II cyclic photophosphorylation. N,N,N'N'-Tetramethyl-p-phenylenediamine catalyzes photosystem II cyclic photophosphorylation at rates approaching those observed with p-phenylenediamine. The activities of both proton/electron and electron donor catalysts of the photosystem II cycle are inhibited by dibromothyoquinone and antimycin A. These findings are interpreted to indicate that photosystem II cyclic photophosphorylation requires the operation of endogenous membrane-bound electron carriers for optimal coupling of ATP synthesis to electron transport.
将 KCN-Hg-NH(2)OH 抑制的菠菜（Spinacia oleracea L.）叶绿体在黑暗中与对苯二胺孵育 10 分钟，然后再进行光照，可使光合系统 II 循环磷酸化的速率比不孵育时提高 2 倍。用铁氰化物部分氧化对苯二胺可产生类似的 ATP 合成刺激；添加二硫苏糖醇可抑制孵育观察到的刺激。添加足以完全氧化对苯二胺的铁氰化物并不能完全抑制光合系统 II 循环活性。这至少部分是由于对苯二胺氧化产生的亚铁氰化物本身就是光合系统 II 循环光磷酸化的催化剂。N,N,N'N'-四甲基对苯二胺以接近与对苯二胺观察到的速率催化光合系统 II 循环光磷酸化。质子/电子和电子供体催化剂的活性都被二溴噻蒽醌和antimycin A 抑制。这些发现的解释表明，光合系统 II 循环光磷酸化需要内源性膜结合电子载体的操作，以实现 ATP 合成与电子传递的最佳偶联。
