Structure and Function of Carotenoids

类胡萝卜素的结构和功能

• 批准号: 1243565
• 负责人: Harry Frank
• 金额: $ 56.79万
• 依托单位: University of Connecticut
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-03-01 至 2017-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1243565&HistoricalAwards=false
• 关键词: Structure; Function; Carotenoids; Structure; Function; Carotenoids

Carotenoids are naturally-occurring pigments that are essential for the survival of photosynthetic organisms. They act as protective devices against irreversible photodestruction of the photosynthetic apparatus, and they function as light-harvesting pigments. Despite this general knowledge of carotenoid behavior obtained from years of investigations, the excited state spectra and dynamics of these molecules are still not well understood. Many of the assignments of their energy states from spectroscopic data are controversial, and the precise nature of the excited states and the roles they play in controlling the biological functions of carotenoids remain unclear. The overall objective of the project is to elucidate the excited state spectra and dynamics of carotenoids in order to reveal how they carry out their important roles in nature. The planned experiments will analyze systematic series of polyenes and carotenoids obtained either synthetically or from several different photosynthetic organisms. In addition, recombinant proteins refolded with modified chlorophylls, or having undergone site-directed mutagenesis in the vicinity of protein-bound pigments, will be studied. Ultrafast time-resolved spectroscopic methods will be used to measure the spectra and dynamics of the excited states. The experiments will be augmented by theoretical quantum mechanical computations to reveal the excited state configurations which will be correlated with the spectroscopic observables. Kinetic and quantum mechanical models describing the photochemical behavior of carotenoids will be evaluated. Various hypotheses pertaining to the excited state structure and spectral properties of carotenoids will be tested, and a number of issues regarding how carotenoids function will be addressed.Broader impactsThe subject of the research has broad relevance to several socially important topics including global climate change, biofuels, and the development of alternative solar energy conversion schemes. A critical aspect of this project will be its impact on the training of undergraduate and graduate students which include those from underrepresented groups recruited though several outreach activities in which the PI will continue to participate. In the laboratory of the PI, the students will gain experience in a broad spectrum of experimental approaches including the techniques for the isolation and characterization of complex biological materials, sophisticated molecular spectroscopic methodologies, and kinetic and quantum computational modeling. The students will develop organizational and problemsolving skills by writing reports and publications and making presentations at scientific meetings to obtain valuable critical feedback from experts in the field. In addition, the PI will advance general understanding of the project by incorporating the subject matter directly into the freshman-level General Chemistry and graduate Biological and Physical Chemistry courses and through outreach activities involving the general public. The PI will be giving presentations at various schools where he will speak not only about the scientific content, but also about the broad social impacts of the project. The PI will continue his active role as a mentor in the NSF-sponsored REU program in the Department of Chemistry where a participating student will work directly on the project. Finally, the PI has established collaborative arrangements with internationally-known experts who will interact freely with the students in the group specifically on work related to this project, offer a global perspective on the work, and help bring the studies to fruition as rapidly as possible.This project is jointly supported by the Molecular Biophysics program in the Division of Molecular and Cellular Biosciences and the Chemical Structure, Dynamics and Mechanism and Chemistry of Life Processes programs in the Chemistry Division

类胡萝卜素是自然存在的色素，对于光合生物的存活至关重要。它们充当防止光合作用的不可逆光电隔离的保护装置，并充当轻度收获的颜料。尽管对从多年研究获得的类胡萝卜素行为进行了普遍了解，但这些分子的激发态光谱和动力学仍然尚不清楚。从光谱数据中，其能量状态的许多分配都是有争议的，激发态的确切性质及其在控制类胡萝卜素的生物学功能中所扮演的作用尚不清楚。该项目的总体目的是阐明类胡萝卜素的激发状态光谱和动力学，以揭示它们如何在自然中发挥重要作用。计划的实验将分析合成或从几种不同的光合生物中获得的多烯和类胡萝卜素系列。此外，将研究用改性叶绿素重折叠的重组蛋白，或者研究在蛋白质结合的颜料附近经过定位的诱变。超快时间分辨的光谱方法将用于测量激发态的光谱和动力学。实验将通过理论量子机械计算来增强，以揭示激发态构型与光谱可观察结果相关的激发态构型。将评估描述类胡萝卜素光化学行为的动力学和量子机械模型。将测试与类胡萝卜素的激发态结构和光谱特性有关的各种假设，并有关如何解决类胡萝卜素功能的许多问题。BROADER影响研究的主题与几个社会重要的主题具有广泛的相关性，包括全球气候变化，生物燃料，生物元素，以及交替的Solar Energy Energy Energy Energy Energy Energy Energy Energy Energy Versansion Seremes的发展。该项目的一个关键方面将是它对本科生和研究生的培训的影响，其中包括来自代表性不足的小组的培训，尽管招募了几项外展活动，PI将继续参加。在PI的实验室中，学生将在广泛的实验方法中获得经验，包括复杂生物材料的隔离和表征，复杂的分子光谱方法论以及动力学和量子计算建模的技术。学生将通过撰写报告和出版物并在科学会议上进行演讲来发展组织和解决问题的技能，以获得该领域专家的宝贵关键反馈。此外，PI将通过将主题直接纳入新生一般化学和研究生生物学和物理化学课程以及涉及公众的外展活动来提高对项目的一般理解。 PI将在各个学校进行演讲，在那里他不仅会谈论科学内容，而且还谈论该项目的广泛社会影响。 PI将继续在化学系的NSF赞助的REU计划中担任导师的积极角色，其中参与学生将直接从事该项目。最后，PI已与国际知名的专家建立了合作安排，他们将在与该项目相关的工作方面自由互动，对工作提供了有关工作的全球视角，并帮助尽快实现研究。该项目是由该项目共同支持的。该项目是由分子和细胞结构的分子生物物质和化学生物学的分工和化学生物学的共同支撑，并且是分子生物和化学生物学的分裂，这些工具和化学生物学的动作效果，这些过程的动作，这些过程，这些过程，这些过程的动作，这种项目的动态，这些计划的动作，这些过程的动作，这些过程的效果，这些项目的效果，这些计划的效果，这些过程的动作，这些过程的效果以及这种项目的效果，这些计划的效果是这种项目的效果。化学部门