IMAGINE: Adaptation of cyanobacterial light harvesting and metal homeostasis traits to environmental change.

蓝细菌是水生食物网中的光合微生物。它们占据着不同类型的环境，从原始的海洋沃茨到高营养，有时是金属污染的海湾。研究人员发现，一种蓝藻物种已经从海洋环境过渡到圣地亚哥湾，这将需要它适应不同的条件，如光线质量和污染的沃茨。他们将检查这种蓝藻中的特定基因是否会因新环境而发生变化，或者蓝藻是否会从其环境中的DNA中获得新基因，以帮助其适应圣地亚哥湾的环境。由于地球的环境正在迅速变化，重要的是要了解生物体，如蓝藻将如何改变响应的机制，以及它们适应能力的限制是什么。这项研究的主要目标是确定蓝藻如何能够适应不同的环境。此外，该项目还将培训一名博士后研究员和一名大学生，学习分子生态学技术。PI还建议与位于丘拉维斯塔的圣地亚哥湾南部的生活海岸探索中心合作，制定一个以微生物学为重点的野生动物日营计划。露营者将发现圣地亚哥湾如何充满并依赖于浮游生物、微生物和其他小物种的世界。该项目的独特之处在于，学生将有机会参与海湾采样，并使用显微镜观察光合微生物。水生微生物可以适应和多样化，以占据新的生态位。对于蓝细菌，光捕获和金属稳态的复杂特性是适应新环境的特性的例子，这些环境具有光质量（颜色）或微量金属量的差异。环境序列数据显示，一个正常的寡营养“物种”的海洋蓝藻，聚球藻分支II，已经越过沿海地区（占主导地位的其他分支），并适应了富营养化的圣地亚哥湾内的条件。这种现象是了解微生物如何在分子水平上适应复杂性状的理想案例研究。使用分离株和流式细胞的单细胞基因组，研究人员将确定是否正选择已经在聚球藻基因组中的特定基因上运作。此外，聚球藻进化枝II菌株也可能通过水平基因转移在圣地亚哥湾获得新基因。基因敲除/敲入将用于测试特定基因的功能优势。PI建议与位于圣地亚哥湾的生活海岸探索中心合作，制定一个以微生物学为重点的野生动物日营计划。露营者将发现圣地亚哥湾是如何充满并依赖于微生物的。该计划将是独一无二的，因为学生将有机会与科学家见面，参观工作实验室，参与海湾采样，并利用光和荧光显微镜观察微生物。该项目还将培训一名博士后研究员和一名大学生，学习分子生态学和进化技术。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Cyanobacteria are photosynthetic microorganisms at the base of aquatic food webs. They occupy different types of environments from pristine ocean waters to high nutrient, sometimes metal-polluted bays. The investigators have found that one cyanobacterial species has transitioned from a marine environment into the San Diego Bay, which would require it to adapt to different conditions such as light quality and polluted waters. They will examine if specific genes in this cyanobacterium changed in response to the new environment or if the cyanobacterium picked up new genes from DNA in its environment to help it adapt to the San Diego Bay environment. Since the earth’s environment is changing rapidly, it is important to understand the mechanisms of how organisms such as cyanobacteria will change in response, and what might be the limits on their ability to adapt. The main goal of this research is to determine how cyanobacteria are able to adapt to different environments. In addition, the project will train a post-doctoral fellow and undergraduates in techniques in molecular ecology. The PIs also propose to develop, in collaboration with the Living Coast Discovery Center in south San Diego Bay in Chula Vista, a program for a Wildlife Day Camp focused on microbiology. Campers will discover how the San Diego Bay is filled with, and dependent on, the world of plankton, microbes, and other small species. This program will be unique in that students will have an opportunity to participate in sampling on the Bay and use microscopes to view photosynthetic microbes.Aquatic microbes can adapt and diversify to occupy new ecological niches. For cyanobacteria, the complex traits of light-harvesting and metal homeostasis are examples of traits that adapt to new environments with differences in light quality (color) or amounts of trace metals. Environmental sequence data show that a normally oligotrophic “species” of marine cyanobacteria, the Synechococcus clade II, has crossed over the coastal zone (dominated by other clades) and adapted to the conditions inside eutrophic San Diego Bay. This phenomenon is an ideal case study for understanding how microbial adaptation of complex traits occurs at the molecular level. Using isolates and single cell genomes of flow-sorted cells, the investigators will determine if positive selection has been operating on specific genes in the Synechococcus genome. In addition, Synechococcus clade II strains may also be acquiring novel genes in San Diego Bay through horizontal gene transfer. Gene knockouts/knockins will be used to test the functional advantage of specific genes. The PIs propose to develop, in collaboration with the Living Coast Discovery Center, located on San Diego Bay, a program for a Wildlife Day Camp focused on microbiology. Campers will discover how the San Diego Bay is filled with, and dependent on, microbes. This program will be unique in that students will have an opportunity to meet scientists, visit working labs, participate in sampling on the Bay and utilize light and epifluorescence microscopes to view microbes. The project will also train a post-doctoral fellow and undergraduates in techniques in molecular ecology and evolution.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.