Biogenesis of thylakoid membranes in cyanobacteria

蓝藻类囊体膜的生物发生

• 批准号: 223817724
• 负责人: Professor Dr. Jörg Nickelsen, Ph.D.
• 金额: --
• 依托单位: Arbeitsgruppe Molekulare Pflanzenwissenschaften
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2012
• 资助国家: 德国
• 起止时间: 2011-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/223817724?language=en
• 关键词: Biogenesis; thylakoid; membranes; cyanobacteria

The thylakoid membrane (TM) represents the site of the energy-producing photosynthetic electron transport via the protein/pigment complexes photosystem II (PSII), Cytb6f and photosystem I (PSI). While the structure and working mode of this molecular machine is well understood, less is known about its development during ontogenesis. This research project is dedicated to the elucidation of the spatial/temporal organization of TM biogenesis in the cyanobacterial model system Synechocystis sp. PCC 6803. As a case study, we will focus on the assembly of PSII, especially its oxygen-evolving manganese cluster, which we have recently been postulated to take place in specialized biogenesis centers close to the plasma membrane. In this regard, the periplasmic PratA factor as well as the gene product of reading frame slr0483 seem to play essential roles. While the tetratricopeptide repeat (TPR) protein PratA transports manganese and, thus, is directly involved in the maturation of the water splitting apparatus of PSII, the membrane protein Slr0483p appears to be generally required for the formation of biogenesis centers based on latest ultrastructural investigations.The goal of the planned work is to gain detailed insights into the molecular working mode as well as the spatial organization of these factors by applying molecular genetical, biochemical/biophysical and electron microscopical methods. In addition other factors like the recently identified PratA interaction partners, i.e., Slr1277p and the Deg-protease HhoA will be analyzed in regard to their function and subcellular localization. Parallel X-ray structure analysis of the PratA/D1 complex will reveal details of the manganese uptake process by the D1 protein of PSII. This work will be complemented by biochemical analyses of PratA-related factors from green algae and vascular plants to test for an evolutionary conserved manganese delivery to PSII.

类囊体膜（TM）代表通过蛋白质/色素复合物光系统II（PSII），CYTB6F和Photosystem I（PSI）通过蛋白质/颜料复合物II（PSII）II（PSI）产生能量的光合电子传输的位点。尽管该分子机器的结构和工作模式已被充分了解，但对其在个体发生过程中的发展知之甚少。该研究项目致力于阐明在蓝细菌模型系统Synechocystis sp。中TM生物发生的空间/时间组织。 PCC 6803。作为案例研究，我们将重点关注PSII的组装，尤其是其氧气不断发展的锰簇，我们最近被认为是在靠近质膜的专用生物发生中心中进行的。在这方面，周质PRATA因子以及阅读框架SLR0483的基因产物似乎起着重要作用。虽然四肽重复（TPR）蛋白PRATA转运锰，因此直接参与了pSII的水分裂设备的成熟，但膜蛋白SLR0483P通常是基于最新的型号，即逐步构建的型号，从而使生物发生中心形成基于生物学中心的季节，这通常是形成生物发生中心的。这些因素通过应用分子遗传，生化/生物物理和电子显微镜方法。此外，还将分析其他因素，例如最近确定的PRATA相互作用伙伴，即SLR1277P和DEG-蛋白酶HHOA的功能和亚细胞定位。 PRATA/D1复合物的平行X射线结构分析将通过PSII的D1蛋白揭示锰吸收过程的细节。这项工作将通过对PRATA相关因素的生化分析来补充，从绿藻和血管植物中，测试了进化保守的锰递送到PSII。