Understanding the role of carotenoids in bacterial light-harvesting proteins

了解类胡萝卜素在细菌光捕获蛋白中的作用

• 批准号: BB/W004593/1
• 负责人: Peter Adams
• 金额: $ 59.25万
• 依托单位: University of Leeds
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FW004593%2F1
• 关键词: Understanding; role; carotenoids; bacterial; light

This project will quantify how "light-harvesting" (LH) proteins can protect photosynthetic organisms from exposure to intense sunlight, in a process called "photo-protection". To do this, we will use genetically-modified versions of the LH proteins and artificial biomembranes that were recently developed by our team. These LH proteins are naturally localised within specialised biomembranes found in photosynthetic bacteria or plant chloroplasts. Bright sunlight can cause damage to plants and photosynthetic bacteria, so, to prevent this they activate photo-protective processes which safely remove the excess energy. This process is essential for fitness of plants and phototrophic bacteria but there are gaps in our knowledge of it. We know that carotenoid pigments are involved and also that the clustering of LH proteins increases energy dissipation, but the molecular details are uncertain. This project will determine how these two factors (carotenoids and protein clustering) can cause photo-protection by comparing LH proteins from photosynthetic bacteria to LH proteins from plants. Samples will be analysed with a world-class suite of microscopy and spectroscopy instruments. Firstly, we will assess how energy dissipation in the LH proteins is related to their carotenoid content for the simplest situation of isolated proteins. Secondly, we will assess how energy dissipation relates to the dual effects of protein clustering and carotenoids using artificial biomembranes which offer us greater control over the system. Thirdly, we will assess natural biomembranes and compare these to the artificial biomembranes to show whether the more complicated native system has other factors which alter the behaviour of LH proteins. Revealing the shared molecular mechanisms for how plants and bacteria control the distribution of energy within LH membranes will help us to understand the critical stages of solar energy capture which are fundamental to the global process of photosynthesis. This could provide new information that helps other researchers develop improved crops that have higher yields.

该项目将量化“光捕获”（LH）蛋白如何保护光合生物免受强烈阳光照射，这一过程称为“光保护”。为此，我们将使用我们团队最近开发的 LH 蛋白的转基因版本和人工生物膜。这些 LH 蛋白天然位于光合细菌或植物叶绿体中的特殊生物膜内。明亮的阳光会对植物和光合细菌造成损害，因此，为了防止这种情况，它们会激活光保护过程，安全地去除多余的能量。这个过程对于植物和光养细菌的适应性至关重要，但我们对此的了解还存在空白。我们知道类胡萝卜素色素参与其中，而且 LH 蛋白的聚集会增加能量耗散，但分子细节尚不确定。该项目将通过比较光合细菌的 LH 蛋白与植物的 LH 蛋白来确定这两个因素（类胡萝卜素和蛋白质簇）如何引起光保护。样品将使用世界一流的显微镜和光谱仪器进行分析。首先，我们将评估 LH 蛋白中的能量耗散与其类胡萝卜素含量的关系，以了解最简单的分离蛋白情况。其次，我们将使用人造生物膜来评估能量耗散与蛋白质聚集和类胡萝卜素的双重效应之间的关系，这使我们能够更好地控制系统。第三，我们将评估天然生物膜并将其与人造生物膜进行比较，以显示更复杂的天然系统是否具有其他改变 LH 蛋白行为的因素。揭示植物和细菌如何控制 LH 膜内能量分布的共同分子机制将有助于我们了解太阳能捕获的关键阶段，这对于全球光合作用过程至关重要。这可以提供新信息，帮助其他研究人员开发产量更高的改良作物。