Chlorophyll a Fluorescence Transients in Mesophyll and Guard Cells : MODULATION OF GUARD CELL PHOTOPHOSPHORYLATION BY CO(2).
Chlorophyll a Fluorescence Transients in Mesophyll and Guard Cells : MODULATION OF GUARD CELL PHOTOPHOSPHORYLATION BY CO(2).
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叶肉和保卫细胞中的叶绿素 a 荧光瞬变：CO(2) 调节保卫细胞的光磷酸化。
DOI：
10.1104/pp.69.3.642
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发表时间：
1982
期刊：
影响因子：
7.4
通讯作者：
Eduardo Zeiger
中科院分区：
文献类型：
--
作者：
Anastasios Melis;Eduardo Zeiger
利用高分辨荧光光谱技术对吊兰杂色叶片的叶肉和保卫细胞叶绿体的荧光瞬变进行了比较。与叶肉细胞一样，保卫细胞叶绿体也表现出OPS荧光瞬变，表明这些细胞器中存在线性电子传递和NADPH的可能产生。它们还显示出缓慢的荧光产额下降，相当于叶肉中的MT跃迁，表明高能态和β磷酸化的形成。与叶肉叶绿体不同，保卫细胞叶绿体的荧光缺乏SM转换的增量，表明两种类型的叶绿体具有一定的代谢差异。CO（2）（以碳酸氢盐形式提供，pH 6.7）的存在特异性地抑制MT-当量转换，而CO（2）的缺乏则加速MT-当量转换。这些观察结果构成保卫细胞叶绿体对CO（2）反应的第一个具体证据。CO（2）对保卫细胞胞质中光合ATP水平的控制可能提供了一种调节保卫细胞质膜高能当量可用性的机制，从而影响气孔开放。
Chlorophyll fluorescence transients from mesophyll and guard cell chloroplasts of variegated leaves from Chlorophytum comosum were compared using high resolution fluorescence spectroscopy. Like their mesophyll counterparts, guard cell chloroplasts showed the OPS fluorescence transient indicating the operation of the linear electron transport and the possible generation of NADPH in these organelles. They also showed a slow fluorescence yield decrease, equivalent to the MT transition in mesophyll, suggesting the formation of the high energy state and photophosphorylation. Unlike the mesophyll chloroplasts, the fluorescence from guard cell chloroplasts lacked the increment of the SM transition, indicating that the two types of chloroplasts have some metabolic differences. The presence of CO(2) (supplied as bicarbonate, pH 6.7) specifically inhibited the MT-equivalent transition while its absence accelerated it. These observations constitute the first specific evidence of a guard cell chloroplast response to CO(2). Control of photosynthetic ATP levels in the guard cell cytoplasm by CO(2) may provide a mechanism regulating the availability of high energy equivalents at the guard cell plasmalemma, thus affecting stomatal opening.