THE PHOTOSYNTHETIC CHROMATOPHORE

光合色素细胞

• 批准号: 8172047
• 负责人: MELIH K SENER
• 金额: $ 6.7万
• 依托单位: UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-01 至 2011-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8172047
• 关键词: Biophysics; Charge; Chemicals; Chromatophore; Complex; Computer Retrieval of Information on Scientific Projects Database; Diffuse; Funding; Grant; Harvest; Institution; Light; Membrane; Organelles; Photons; Process; Production; Proteins; Proteobacteria; Protons; Quinones; Reaction; Research; Research Personnel; Resources; Rhodobacter sphaeroides; Shapes; Source; Tube; United States National Institutes of Health; Vesicle; absorption; dimer

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The chromatophore is a pseudo-organelle that is responsible for harvesting light and subsequent conversion of light energy to chemical energy in the form of ATP (http://www.ks.uiuc.edu/Research/psures). After initial excitation from photon absorption by the light harvesting proteins in the chromatophore, excitation energy is tranferred in a multi-step process to a reaction center (RC). At the RC the excitation energy is used to charge a quinone molecule, which then diffuses through the protein-rich chromatophore membrane to a bc$_1$. There the charged quinone is oxidized yo produce a proton gradient across the membrane, which in turn drives ATP production by ATP synthase. In purple bacteria, such as Rhodobacter sphaeroides, the protein responsible for photon capture are known as light harvesting complex 1 (LH1) and light harvesting complex 2 (LH2). LH1 associates with two other proteins found in the chromatophore, RC and PufX, to form LH1-RC-PufX dimer complexes. LH2 and LH1-RC-PufX have a dual function; not only are they responsible for capturing light energy, they also induce membrane curvature to shape the chromatophore into, e.g., vesicles or tubes. Therefore, the systemis relevant to understand two fundamental questions in biophysics, namely membrane morphonegensis and cellular energy production.

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。子项目及 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以在其他 CRISP 条目中表示。列出的机构是 对于中心来说，它不一定是研究者的机构。 色素细胞是一种伪细胞器，负责收集光和随后的转换 光能转化为 ATP 形式的化学能 (http://www.ks.uiuc.edu/Research/psures)。初始激励后 通过色素细胞中的光捕获蛋白吸收光子，激发能量以 到反应中心（RC）的多步骤过程。在 RC 处，激发能用于给醌分子充电，这 然后通过富含蛋白质的色素细胞膜扩散到 bc$_1$。那里带电的醌被氧化了哟 产生跨膜质子梯度，进而驱动 ATP 合成酶产生 ATP。在紫色细菌中， 例如球形红杆菌，负责光子捕获的蛋白质被称为光捕获复合物 1 (LH1) 和光捕获复合物 2 (LH2)。 LH1 与色素细胞中发现的另外两种蛋白质 RC 和 PufX，形成 LH1-RC-PufX 二聚体复合物。 LH2和LH1-RC-PufX具有双重功能；他们不仅负责 在捕获光能的同时，它们还会引起膜弯曲，从而将色素细胞塑造成囊泡或管状等。 因此，该系统与理解生物物理学中的两个基本问题相关，即膜 吗啡生成和细胞能量产生。