Control mechanisim of the electron transport in chloroplasts

Saeki等人。利用基因工程技术构建了突变的囊状隐孢子虫fdxN。他们确定了活动所必需的半胱氨酸残基。EPR谱表明，Fe-S团簇周围的氨基酸残基对自旋相互作用有很强的影响。他还证明了fdxA产物在[3Fe-4S]簇和羧基末端区域的结构对生理功能是重要的。已经成功地纯化了由两个亚基组成的氯离子反应中心复合体(CRC-2)，即核心蛋白(68 KDa)和细胞色素C551(21 KDa)。激光闪光光解发现了光解过程中的第一次电荷分离，以及伴随着P840^T形成的延迟荧光。他们还克隆了细胞色素C551基因，并打算建立绿色菌转化体系。在兔子体内产生了针对它们的抗体。各抗体均表现出特异性，无交叉反应。抗体从萝卜的根和叶以及其他开花植物中区分出酶的形式。FNR同工酶呈器官特异性分布，Buchanan报道胚乳中硫氧还蛋白的水平在萌发过程中可能受激素控制。他还证明了菠菜硫氧还蛋白m抑制了非洲爪哇受精卵中DNA的合成。马尔金最近克隆了编码Rieske蛋白的PETC。他打算构建PETC的定点突变，以便用EPR技术研究循环电子传递。

Saeki et al. have constructed mutated fdxN of R. capsulatus with gene-engineering techniques. They identified cysteine residues essential to activity. With EPR spectroscopy, the spin interaction was found to be strongly affected by the amino acid residues around Fe-S clusters. He also demonstrated that the structures of fdxA product around [3Fe-4S] cluster and carboxyl terminal region were important to function physiologically.Oh-oka et al. have succeeded in purifying the Chlorobium reaction center complex (CRC-2) made of two subunits, that is, the core protein (68kDa) and cytochrome c551(21kDa), respectively. Laser flash photolysis revealed the primary charge separation, followed by the delayed fluorescence concomitant with the formation of P840^T. They also have cloned the cytochrome c551 gene, and intend to construct transformation system in Chlorobium.Wada have isolated two FNR isoenzymes from radish leaf and root. Antibodies against them were raised in rabbits. Each antibody showed specific reactivity and had no cross-reactivity. The antibodies distinguished the enzyme forms from roots and leaves of radish as well as other flowering plants. The FNR isoenzymes showed organ-specific distribution.Buchanan reported that the level of thioredoxin in the endosperm might be under hormonal control during germination. He also demonstrated that spinach thioredoxin m inhibits DNA synthesis in fertilized Xenopus eggs.Malkin have recently cloned the petC, which encoded Rieske protein. He intends to construct site-directed mutagenesis of the petC in order to study the cyclic electron transport with EPR technique.