Collaborative research: Characterization of Synechococcus-cyanophage interactions across phylogenetic and temporal scales

合作研究：跨系统发育和时间尺度的聚球藻-噬藻体相互作用的表征

• 批准号: 2023175
• 负责人: Nathan Ahlgren
• 金额: $ 72.48万
• 依托单位: Clark University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-12-01 至 2024-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2023175&HistoricalAwards=false
• 关键词: Collaborative; research; Characterization; Synechococcus; cyanophage

Viral infection influences the flow of nutrients in the oceans and the diversity and structure of ecologically important microbial communities. Understanding which viruses infect which hosts is critical to understanding the exact impact of viruses, but there are still critical gaps in knowledge about how widely viruses can infect specific bacteria types and how this can change over time. This project includes the isolation and characterization of hundreds of co-occurring photosynthetic bacteria (cyanobacteria from the genus Synechococcus) and viruses that infect them (cyanophage) from Narragansett Bay, Rhode Island to assess the degree to which they can infect each other and identify specific genes that control cross-infection. DNA collected for over 10 years from Narragansett Bay is used to track Synechococcus and cyanophage communities to determine how virus-host interactions play out in shaping the diversity of natural Synechococcus and cyanophage communities over seasonal cycles and from year to year. This work provides knowledge of how individual viral-host interactions in a natural community can lead to the stable co-existence of particular species of viruses and bacteria in a coastal ecosystem over time. This project supports 15 undergraduate student researchers, a graduate student and a postdoctoral fellow who also receives training in effective practices in science teaching. Integration of the study’s results into undergraduate courses and outreach activities facilitates authentic opportunities for students to contribute to research and engagement of local junior and senior high school students.The team of scientists and students are conducting a phylogenetically-informed study of natural communities of co-occurring Synechococcus and cyanophage, a model tractable system in Narragansett Bay, to characterize phage-host interactions across different scales of diversity and time. The team’s goal is to isolate a large collection of ~100 Synechococcus and ~200 cyanophage from Narragansett Bay and to conduct infection assays and comparative genomics on these isolates. They employ amplicon sequencing of highly variable loci for both Synechococcus and cyanophage to characterize community dynamics across broad to fine genetic scales—ecotypes to within-species variants—for 10 years of archived monthly samples and a new weekly time-series over two years. These studies address the following three key questions: 1) Are there inherent boundaries of genetic relatedness (i.e. ecotype, species, or finer levels) at which the patterns of infection networks fundamentally shift from being mostly nested to mostly modular? (2) What are the underlying mechanisms and genetic loci that determine the boundaries of infection, i.e., host range and phage susceptibility? and, (3) How do host-phage interactions at different phylogenetic levels influence community structure over short (weeks to months) and long (year-to-year) time scales? Results from this project help to better understand how phytoplankton and bacterioplankton communities are shaped by viral predation and how host and phage diversity is created, maintained, and structured in the oceans.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.

病毒感染会影响海洋中的养分流以及生态上重要的微生物群落的多样性和结构。了解哪种病毒感染了哪些宿主对于理解病毒的确切影响至关重要，但是在了解广泛的病毒可以感染特定细菌类型以及如何随着时间的推移会改变时仍然存在关键的差距。该项目包括将数百种同时发生的光合细菌（来自Synechococcus属的蓝细菌）的隔离和表征以及感染了它们（cyanophage）的病毒（cyanophage），来自罗德岛州罗德岛州的纳拉甘西特湾（Narragansett Bay），以评估他们彼此感染并识别控制交叉注射的特定基因的程度。从Narragansett Bay收集了10多年的DNA用于跟踪杂技演环和氰基社群社区，以确定病毒宿主相互作用如何在季节性周期和季节性周期和激发自然的综合群体和氰基社区的多样性方面发挥作用。这项工作提供了有关自然社区中各个病毒宿主相互作用如何导致特定物种和细菌在沿海生态系统中的稳定共存的知识。该项目支持15名本科生研究人员，研究生和博士后研究员，他们还接受了科学教学有效实践的培训。 Integration of the study’s results into undergraduate courses and Outreach activities facilitates authentic opportunities for students to contribute to research and engagement of local junior and senior high school students.The team of scientists and students are conducting a phylogenically-informed study of natural communities of co-occurring Synechococcus and cyanophage, a model tractable system in Narragansett Bay, to characterize phage-host interactions across different scales of diversity和时间。该团队的目标是隔离纳拉甘塞特湾（Narragansett Bay）大量约100张综合菌和约200个氰基，并对这些分离株进行感染评估和比较基因组学。他们采用高度可变的位置进行了合成菌和氰化物的放大测序，以表征跨越宽至细遗传尺度的社区动力学（包括在物种内部变体中的型号），共10年的每月样本和两年内的新每周时间表。这些研究解决了以下三个关键问题：1）是否存在遗传相关性的固有界限（即生态型，物种或最终水平），在该遗传相关性，感染网络的模式从根本上从大部分嵌套到大多数模块化？ （2）确定感染边界的基本机制和遗传环境是什么，即宿主范围和噬菌体敏感性？ （3）在不同的系统发育水平上的宿主阶段相互作用如何影响短期（几周至几个月）和漫长（每年）时间尺度的社区结构？该项目的结果有助于更好地了解植物浮游生物和细菌浮游生物社区如何受病毒呈现的影响，以及如何在海洋中创建，维护和构建宿主和噬菌体多样性。这项奖项反映了NSF的法定任务，并通过使用该基金会的知识分子优点和广泛的影响来评估NSF的法定任务，并被认为是珍贵的支持。