In the belly of the whale: endobionts inhabit the world's largest bacteria

在鲸鱼的腹部：内生生物栖息在世界上最大的细菌中

• 批准号: 1935351
• 负责人: Jake Bailey
• 金额: $ 79.77万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-03-01 至 2025-02-28
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1935351&HistoricalAwards=false
• 关键词: belly; whale; endobionts; inhabit; world

Mitochondria and chloroplasts, the organelles that provide energy to the eukaryotic cell, are thought to have evolved more than two billion years ago from symbiotic bacteria that lived within a microbe. Despite their potential to help in the understanding of eukaryote evolution, examples of bacteria that host other bacteria are very rare. The principal investigators recently discovered a population of giant bacteria that host dense populations of bacteria within their cells. The investigators will study the community of bacteria associated with the giant bacteria, determine how certain bacteria enter the host cells, and explore the interactions among the intracellular bacteria and the giant host cell. This system provides a unique opportunity to gain an understanding of this host bacterium-bacteria symbioses. In addition to exploring basic aspects of eukaryotic evolution and microbial interactions, the investigators will provide field and laboratory experiences for U.S. military veteran students, U.S. high school students, and students from Namibia, bringing the students together in a novel exchange program. This international partnership will not only help train U.S. student veterans in STEM fields, and high school students from underrepresented groups, but also help to expand the research capabilities of sub-Saharan Africa by training students in cutting-edge approaches to studying fundamental cell processes.Endosymbiotic relationships involving prokaryotic host cells and other prokaryotes are extremely rare and not well understood. The investigators recently discovered a population of metabolically active giant sulfur bacteria cells, Thiomargarita spp., that contain dense populations of intracellular bacteria. Some of these bacteria are related to known animal endosymbionts but the structure and ecology of these intracellular bacterial communities is still incomplete. To better understand the host bacterium-bacteria symbioses, the investigators are (1) investigating the microbial community structure associated with different phylotypes of Thiomargarita spp., 2) identifying the potential mechanism(s) by which cells enter Thiomargarita spp., and 3) studying ecological and physiological interactions between the endobiont bacteria and Thiomargarita spp. In order to investigate potential interactions between host Thiomargarita spp. cells and their endobionts, as well as to characterize the community compositions, a set of diverse techniques, such as metagenomics, metatranscriptomics, and fluorescence in situ hybridization, are being employed. In addition, infection challenge experiments are being performed to elucidate the potential mechanisms by which the endobiont(s) becomes internalized within the host cell. This research has the potential to provide insights into eukaryotic evolution and the interactions that underlie the host prokaryote-endosymbiotic prokaryotes symbioses.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.

线粒体和叶绿体是为真核细胞提供能量的细胞器，被认为从微生物内的共生细菌中进化了超过20亿年。尽管它们有可能帮助理解真核生物的进化，但携带其他细菌的细菌的例子非常罕见。主要研究人员最近发现了一群巨细菌群，它们在其细胞中占地密集的细菌群。研究人员将研究与巨细菌相关的细菌群落，确定某些细菌如何进入宿主细胞，并探索细胞内细菌和巨型宿主细胞之间的相互作用。该系统提供了一个独特的机会来了解这种宿主细菌 - 细菌共生菌。除了探索真核进化和微生物互动的基本方面外，研究人员还将为美国军事退伍军人学生，美国高中学生和纳米比亚的学生提供现场和实验室经验，将学生聚集在一起。这种国际合作伙伴关系不仅将帮助培训来自代表性不足的群体的高中生在STEM领域的培训，而且还可以通过培训学生研究基本细胞过程的尖端方法来扩大撒哈拉以南非洲的研究能力。涉及定核病的宿主和其他原始企业的亲生关系，并且不太罕见。研究人员最近发现了代谢活跃的巨型硫细菌细胞硫代核细菌，其中含有密集的细胞内细菌。这些细菌中的一些与已知的动物内共生体有关，但是这些细胞内细菌群落的结构和生态仍然不完整。为了更好地理解宿主细菌 - 细菌 - 细菌共生菌，（1）研究了与硫代术属的不同类型相关的微生物群落结构，2）识别细胞进入硫代术属的潜在机制，以及3）研究生态和生理学相互作用，研究生态和生理学相互作用。为了研究宿主硫玛加利塔属spp之间的潜在相互作用。细胞及其内向体以及表征社区组成的表征，采用了一系列不同的技术，例如宏基因组学，metatranscriptomics和荧光原位杂交。此外，正在进行感染挑战实验，以阐明内向于内向于内在宿主细胞内化的潜在机制。这项研究有可能提供对真核进化的见解，以及主机原核 - 再生生物生物生物原核生物共生的基础。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子和更广泛影响的审查审查标准来通过评估来通过评估来获得支持的。