腺嘌呤核苷酸对叶绿体中氢离子转运的影响。
Effects of adenine nucleotides on hydrogen-ion transport in chloroplasts.
作者信息
McCarty R E, Fuhrman J S, Tsuchiya Y
出版信息
Proc Natl Acad Sci U S A. 1971 Oct;68(10):2522-6. doi: 10.1073/pnas.68.10.2522.
1-10 muM ATP stimulated H(+) uptake and slowed the release of H(+) in the dark in chloroplasts illuminated at pH values at which photophosphorylation can occur, but not at pH 6.5. This ATP stimulation of H(+) uptake was abolished by an antiserum to the chloroplast coupling factor and was reduced by the energy transfer inhibitors phlorizin and Dio-9. ATP synthesis after illumination was also enhanced by ATP. Electron flow from water to methyl viologen was inhibited by the same low concentrations of ATP.ADP also increased the extent of H(+) uptake in chloroplasts, even in the presence of arsenate and MgCl(2). In the presence of hexokinase and glucose, as well as arsenate and Mg(++), ADP inhibited H(+) uptake. The failure of previous investigators to observe a direct inhibition of H(+) uptake by phosphorylation was probably caused by a masking of the inhibition by the stimulation of H(+) uptake by ATP. Furthermore, the stimulation of H(+) uptake by ATP provides an explanation for its inhibition of electron flow.
在光磷酸化能够发生的pH值条件下，1 - 10微摩尔ATP在黑暗中刺激叶绿体对H⁺的摄取并减缓H⁺的释放，但在pH 6.5时则不然。这种ATP对H⁺摄取的刺激作用被针对叶绿体偶联因子的抗血清消除，并被能量转移抑制剂根皮苷和Dio - 9减弱。光照后的ATP合成也被ATP增强。从水到甲基紫精的电子流被相同低浓度的ATP抑制。即使在存在砷酸盐和MgCl₂的情况下，ADP也增加了叶绿体中H⁺摄取的程度。在己糖激酶、葡萄糖以及砷酸盐和Mg²⁺存在的情况下，ADP抑制H⁺摄取。先前研究人员未能观察到磷酸化对H⁺摄取的直接抑制作用，可能是由于ATP对H⁺摄取的刺激作用掩盖了这种抑制。此外，ATP对H⁺摄取的刺激作用为其对电子流的抑制提供了解释。
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