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“捕光”（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蛋白和人工生物膜的遗传修饰版本。这些LH蛋白天然定位于光合细菌或植物叶绿体中发现的专门生物膜内。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，它们激活了光保护过程，安全地去除多余的能量。这一过程对于植物和光合细菌的适应性是必不可少的，但我们对它的认识还存在空白。我们知道类胡萝卜素色素参与其中，LH蛋白的聚集也增加了能量耗散，但分子细节尚不确定。本研究将通过比较光合细菌LH蛋白和植物LH蛋白来确定这两个因素（类胡萝卜素和蛋白质簇）如何引起光保护作用。将使用世界一流的显微镜和光谱仪器对样品进行分析。首先，我们将评估LH蛋白中的能量耗散如何与分离蛋白的最简单情况下的类胡萝卜素含量相关。其次，我们将评估能量耗散如何与蛋白质聚集和类胡萝卜素的双重作用有关，使用人工生物膜，这为我们提供了对系统的更大控制。第三，我们将评估天然生物膜，并将其与人工生物膜进行比较，以显示更复杂的天然系统是否具有改变LH蛋白行为的其他因素。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，这是全球光合作用过程的基础。这可以提供新的信息，帮助其他研究人员开发具有更高产量的改良作物。