Molecular Organization of Photosystem II Reaction Center

光系统II反应中心的分子组织

• 批准号: 06404003
• 负责人: SATOH Kimiyuki
• 金额: $ 16.7万
• 依托单位: Okayama University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06404003/
• 关键词: Photosynthesis; Photosystem II; Reaction Center; Synechocystis; Mutagenesis; Chlamydomonas; P-680; Processing Protease; クラシドモナス; 分子構築; FTIR

Dynamic as well as static organization of molecules in the photosystem II reaction center was analyzed in this project.I.Structure of isolated photosystem II reaction center(1) Both subunit stoichiometry and pigment stoichiometry of the isolated photosystem II reaction center were re-evaluated in this study using refined techniques.(2) beta-Carotenes in the purified photosystem II reaction center were selectively extracted with diethyl ether containing varied amount of water and the organization and interaction of pigments in the reaction center were analyzed using materials with different pigment contents.(3) The contribution of a pheophytin molecule in inactive branch of electron transport system in the absorption spectrum of photosystem II reaction center was analyzed by fluorescence excitation spectroscopy as well as by absorption, linear dichroism and magnetic circular dichroism spectra. The results were discussed in the light of current understanding of the molecular organization … More in photosystem II raction center.II.Dynamic aspects(1) The light-regulated synthesis of the D1 subunit of photosystem II reaction center was analyzed using isolated pea chloroplasts. In that study we have found that the translation of D1 protein is regulated at the specific steps of polypeptide elongation by a redox factor (s) that is activated by the reduction via photosystem I.We also have succeeded in partially purifying this factor.(2) The enzyme involved in the C-terminal processing of precursor D1 protein was purified from sonicated extracts of thylakoids, by a method that includes chromatography on QAE-anion exchange, hydroxylapatite, Cu-chelating affinity and gel-filtration columns. Based on the amino acid sequence data of the purified protease, a cDNA clone encoding the enzyme was identified and sequenced, from a spinach green leaf cDNA library. By these analyzes, the full-length transcript was established to consist of 1906 nucleotides and a poly (A) tail, containing an open reading frame (ORF) corresponding to a protein with 539 amino acid residues. By comparing the amino acid sequence of the purified protease with that deduced from nucleotide sequence of the cDNA clones, the enzyme was shown to be furnished with an extra N-terminal extension consisted of 150 amino acids which is characteristic of both a transit peptide and a signal sequence. The mechanism of enzymatic catalysis was analyzed using enzymes over-expressed in E.coli. Less

本项目对光系统II反应中心分子的动态和静态组织进行了分析。一、分离的光系统II反应中心的结构(1)本研究采用精细技术重新评估了分离的光系统II反应中心的亚基化学计量和色素化学计量。(2)选择性提取了纯化的光系统II反应中心中的β-胡萝卜素 (3)采用荧光激发光谱、吸收光谱、线性二色性和磁圆二色性分析了电子传递系统非活性支链中脱镁叶绿素分子对光系统II反应中心吸收光谱的贡献。 光谱。根据目前对光系统II反应中心分子组织的理解，对结果进行了讨论。二、动力学方面(1)利用分离的豌豆叶绿体对光系统II反应中心D1亚基的光调节合成进行了分析。在该研究中，我们发现 D1 蛋白的翻译在多肽延伸的特定步骤中受到氧化还原因子的调节，该氧化还原因子通过光系统 I 的还原而被激活。我们还成功地部分纯化了该因子。(2) 通过包括层析在内的方法，从类囊体的超声提取物中纯化了参与前体 D1 蛋白 C 末端加工的酶。 QAE-阴离子交换、羟基磷灰石、Cu-螯合亲和柱和凝胶过滤柱。根据纯化蛋白酶的氨基酸序列数据，从菠菜绿叶 cDNA 文库中鉴定并测序了编码该酶的 cDNA 克隆。通过这些分析，确定全长转录物由 1906 个核苷酸和一条聚 (A) 尾组成，其中包含与具有 539 个氨基酸残基的蛋白质相对应的开放阅读框 (ORF)。通过将纯化的蛋白酶的氨基酸序列与从cDNA克隆的核苷酸序列推导的氨基酸序列进行比较，显示该酶具有由150个氨基酸组成的额外N末端延伸，其是转运肽和信号序列的特征。使用大肠杆菌中过度表达的酶分析酶催化机制。较少的

项目成果

Takahashi.Y.,H.Matsumoto M.Goldschmidt-Clermont and J.-D.Rochaix: "Directed disruption of the Chlamydomonas chloroplast psbk gene destabilizes the photosystem II reaction center complex." Plant.Mol.Biol.24. 779-788 (1994)

Takahashi.Y.、H.Matsumoto M.Goldschmidt-Clermont 和 J.-D.Rochaix：“直接破坏衣藻叶绿体 psbk 基因会破坏光系统 II 反应中心复合体的稳定性。”

Narusaka,Y.et al.: "Preliminary characterization of a photo-tolerant mutant of Synechocystis sp. PCC 6803 obtained by in vitro random mutagenesis of psbA2" Plant Sci.115. 261-266 (1996)

Narusaka,Y.et al.：“通过 psbA2 体外随机诱变获得的集胞藻 PCC 6803 耐光突变体的初步表征”Plant Sci.115。

Fujita,S..,N.Inagaki,Y.Yamamoto,F.Taguchi,A.Matsumoto and K.Satoh: "Identification of the carboxyl-terminal processing protease for Dl precursor protein of photosystem II reaction center of spinach." Plant Cell Physiol.36. 1169-1177 (1995)

Fujita,S..,N.Inagaki,Y.Yamamoto,F.Taguchi,A.Matsumoto 和 K.Satoh：“菠菜光系统 II 反应中心 D1 前体蛋白的羧基末端加工蛋白酶的鉴定。”

Narusaka,Y.,K.Utsumi,Y.Yamamoto,A.Hatano and K.Satoh: "Characterization of a photo-tolerant mutant of Synechocystis sp.PCC 6803 created by in vitro random mutagenesis of psbAII." Plant Sci.(in press). (1996)

Narusaka，Y.，K.Utsumi，Y.Yamamoto，A.Hatano 和 K.Satoh：“通过 psbAII 体外随机诱变产生的集胞藻属 sp.PCC 6803 耐光突变体的表征。”

Narusaka,Y.et al.: "Preliminary characterization of a photo-tolerant mutant of Synechocystis sp.PCC 6803 obtained by in vitro random mutagenesis of psbA2" Plant Sci.115. 261-266 (1996)

Narusaka,Y.et al.：“通过 psbA2 体外随机诱变获得的集胞藻属 sp.PCC 6803 耐光突变体的初步表征”Plant Sci.115。