Molecular and structural biology of phycocyanobilin:ferredoxin oxidoreductases

智力优势：藻胆蛋白是一种色素，在从单细胞藻类到绿色植物的产氧光合作用生物中发挥着重要的捕光作用。当结合到蛋白质(胆蛋白)上时，植物胆蛋白获得光能来驱动蓝绿藻、红藻和褐藻的光合作用，并触发对在不断波动的光环境中生存至关重要的适应性信号通路。该项目的重点是铁氧还蛋白依赖的胆碱还原酶(FDBRs)，这是一个金属自由基酶家族，负责合成这两类光传感器蛋白的植物胆红素前体。本研究利用多种生化和生物物理技术，结合X射线结晶学、分子生物学和生化分析，在分子水平上阐明FDBR的功能。这些知识对于开发FDBRs的激活剂/抑制剂是必要的，这种激活剂/抑制剂可用于增强地球上所有生命所依赖的放氧光合作用生物体的光感知、生长和发育。这些研究还试图了解一种独特的FDBR基因在绿藻衣藻中的生物学作用。莱茵衣藻是一种氧气光合作用有机体，缺乏所有已知的感光胆蛋白。利用对这种生物的遗传、基因组和表型分析，将评估关于该基因功能的几个假说。预计这样的研究将有助于深入了解迄今为止尚未认识到的胆林代谢的新功能。由于衣藻保留了植物和动物的共同特征，这项研究不仅有望为提高作物产量提供新的途径，而且可能揭示与人/动物生理和疾病相关的新的依赖于BLIN的调控途径。这一研究项目的更广泛影响将通过培训各级科学家(博士后、研究生、本科生和高中生)分子生物学、酶学、蛋白质化学、结构生物学、计算生物学和反向遗传学的方法，将研究和教育结合起来。本科生(包括一名代表不足的少数族裔学生)将进行这项研究的多个方面。此外，为了扩大代表不足的群体的参与和PTO远程教学，实验室参与了一些发展和少数民族培训计划，包括：MURPPS(少数民族本科生参与物理科学研究)，Shopch(科学与工程本科生暑期研究计划)，BUSP(生物学本科生学者计划)，以及高中计划，包括青年学者计划，SEED(卓越工程成功计划)和Davis高中高级生物技术课程。

Intellectual merit: Phytobilins are pigments that perform significant light harvesting roles in oxygenic photosynthetic organisms from unicellular algae to green plants. When attached to proteins (biliproteins), phytobilins harvest light energy to drive photosynthesis in blue-green, red and brown algae, and trigger adaptive signaling pathways vital to survival in a constantly fluctuating light environment. This project focuses on ferredoxin-dependent bilin reductases (FDBRs), a family of metal-free radical enzymes that are responsible for the synthesis of phytobilin pigment precursors of both classes of light sensor proteins. Using a variety of biochemical and biophysical techniques, this research seeks to elucidate FDBR function at the molecular level via a combination of x-ray crystallography, molecular biology and biochemical analysis. Such knowledge is needed for development of activators/inhibitors of FDBRs that can be used to enhance light perception, growth and development of oxygen-evolving photosynthetic organisms upon which all life on earth depends. These studies also seek to understand the biological role of a unique FDBR gene in the green alga Chlamydomonas reinhardtii, an oxygenic photosynthetic organism that lacks all known light sensing biliproteins. Using genetic, genomic and phenotypic analyses of this organism, several hypotheses for the function of this gene will be assessed. It is anticipated that such studies will lead to insight into new functions of bilin metabolism hitherto unrecognized. Since Chlamydomonas retains features common to plants and animals, this research is expected not only to yield new avenues to improve crop productivity, but could reveal novel bilin-dependent regulatory pathways of relevance to human/animal physiology and disease. The broader impact of this research project will integrate research and education by training scientists at all levels (postdocs, graduate, undergraduate and high school students) in the methods of molecular biology, enzymology, protein chemistry, structural biology, computational biology and reverse genetics. Undergraduates (including an underrepresented minority student) will conduct a number of aspects of this research. Additionally, to broaden participation of underrepresented groups and pto romote teaching, the labs participate in a number of development and minority-training programs, including: MURPPS (Minority Undergraduate Research Participation in the Physical Sciences), SURPRISE (Summer Undergraduate Research Program In Science and Engineering), BUSP (Biology Undergraduate Scholars Program), and in high school programs including Young Scholar Program, SEED (Success in Engineering through Excellence and Diversity Program), and Davis high school advanced biotechnology class.This project is being supported by the Biomolecular Systems cluster in MCB and the Inorganic, Bioinorganic, and Organometallic Chemistry program in CHE.