过刊浏览

低浓度尼日利亚菌素或氯化铵促进ATP形成机理的再探

卫瑾, 李有则

中科院上海植物生理研究所.上海 200032

摘要

在低盐介质中,含有垛叠类囊体(基粒)与不垛叠类囊体(间质片层)结构的叶绿体进行的光系统Ⅰ电子传递与磷酸化反应(PSP)都为低浓度的尼日利亚菌素所促进,低浓度的氯化铵对基粒结构叶绿体的系统Ⅰ与包括两个系统的电子传递以及与之相偶联的磷酸化反应有促进效应,而对间质片层膜上进行的PSP反应无影响。尼日利亚菌素或氯化铵对PSP的促进效应在高盐介质中消失,且它们对高能态(Z~(*))形成的抑制效应在低盐介质中较高盐介质中大。当存在的吡啶时,在低盐介质中它们对Z~(*)形成的影响是抑制作用,在高盐介质中则是促进效应。这都表明不同结构的膜上均存在区域化质子。

关键词： 尼日利亚菌素; 氯化铵; 膜上区域化质子; 光合磷酸化反应

Further studies on the mechanism of stimulation of ATP formation by nigericin or ammonium chloride at low concentrations

Wei Jin, Li Youze

Shanghai Institute of Plant physiology,The Chinese Acakemy of Sciences. Shanghai 200032

Abstract

The results obtained were as follows:(1)The photophosphorylation activity and electron transport activity of PSⅠin both stacked and unstacked thylakoids of chloroplast were stimulated by low concentrations of nigericin in a low salt medium.(2)Only in the stacked thylakoids had low concentration of NH_4C1 a stimulative effect on the activity of cyclic or noncyclic PSP and that of electron transport through PS Ⅰor through both PS Ⅱ and PSⅠin low salt medium.(3)The stimulative effect of nigericin or NH_4C1 on PSP was not observed in high salt medium.(4)The inhibitory effect of nigericin or NH_4C1 on the formation of the high endergy state was greater in low salt medium than in high salt medium.(5)In low salt medium pyridine decreased the inhibitory effect of nigericin or NH_4C1 to stimmulate the formation of high energy state.These results show that localized protons exist in the stacked and unstacked thylakods,it may be transformed into the delocalized form.

Key words: Nigericin;NH_(4)Cl;Membrane-localized proton;Photophosphorylation

收稿日期：　　录用日期：

通讯作者：　　E-mail:

引用本文：

卫瑾, 李有则. 低浓度尼日利亚菌素或氯化铵促进ATP形成机理的再探[J]. 生理学报 1996; 48 (2): .

Wei Jin, Li Youze. Further studies on the mechanism of stimulation of ATP formation by nigericin or ammonium chloride at low concentrations. Acta Physiol Sin 1996; 48 (2): (in Chinese with English abstract).