Interactions between envelope stress responses, bacteriophages and the environment

包膜应激反应、噬菌体和环境之间的相互作用

• 批准号: RGPIN-2021-02710
• 负责人: Raivio, Tracy
• 金额: $ 4.23万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=742169
• 关键词: Interactions; between; envelope; stress; responses

Like animals and plants, bacteria are subject to viral infections. Bacterial viruses are called bacteriophages and they are thought to inhabit all environments on Earth in concentrations much higher than those of the bacteria they infect. One reason for this is that a type of bacterial viruses called temperate bacteriophages can infect bacteria and integrate into their chromosomes, where they can live quiescently for many generations before becoming active again. Most bacteria are thought to contain temperate bacteriophages in their genomes. The liberation of temperate bacteriophages from the bacterial chromosome results in the production of many new viruses and the infection and killing of neighbouring susceptible microbes, thus providing a competitive advantage to bacterial populations harbouring such viruses. This is important, since most bacteria live in surface-associated communities with many other microbes where they compete for space and resources and are exposed to environmental stressors that threaten their livelihoods. This is true for Escherichia coli, an inhabitant of the large intestine of animals. En route to, and within the intestine, E. coli must withstand many potentially lethal conditions, including toxic antimicrobial substances produced by our bodies and bacteriophages produced by resident commensal microbes. In order to survive, E. coli uses multiple envelope stress responses to detect and respond to these potentially lethal substances. I hypothesize that bacterial envelope stress responses are sensitive to bacteriophage and that they alter the microbial cell in ways that impact the course of bacteriophage infection and/or the ability to survive stress. I further predict that bacteriophages interact with and alter the E. coli envelope and its genetic network to impact stress adaptive functions. My lab discovered and characterized a new temperate bacteriophage called Kapi1 in a recently isolated "wild" strain of E. coli from a mouse digestive tract. We will use our expertise in bacterial genetics and the study of envelope stress responses to initiate a new research program to investigate how bacteriophages and bacteria interact with each other to influence microbial fitness and stress adaptation. Our work will inform future efforts to control and harness bacteria in the environment, for industrial use, and to improve human and animal health.

像动物和植物一样，细菌也会受到病毒感染。细菌病毒被称为噬菌体，它们被认为栖息在地球上的所有环境中，浓度远远高于它们感染的细菌。其中一个原因是，一种被称为温和噬菌体的细菌病毒可以感染细菌并整合到它们的染色体中，在那里它们可以安静地生活许多代，然后再次变得活跃。大多数细菌被认为在它们的基因组中含有温和的噬菌体。温和噬菌体从细菌染色体中释放出来，导致许多新病毒的产生以及邻近易感微生物的感染和杀死，从而为携带此类病毒的细菌群体提供了竞争优势。这一点很重要，因为大多数细菌与许多其他微生物生活在表面相关的社区中，在那里它们争夺空间和资源，并暴露于威胁其生计的环境压力。对于大肠杆菌来说也是如此，大肠杆菌是动物大肠的居民。E.大肠杆菌必须承受许多潜在的致命条件，包括我们的身体产生的有毒抗菌物质和常驻肠道微生物产生的噬菌体。为了生存，E。大肠杆菌利用多重包膜应激反应来检测和应对这些潜在的致命物质。我假设细菌包膜应激反应对噬菌体敏感，并且它们以影响噬菌体感染过程和/或在应激中生存的能力的方式改变微生物细胞。我进一步预测，噬菌体与E.大肠杆菌外膜及其遗传网络对胁迫适应功能的影响。我的实验室在最近分离出的一种“野生”大肠杆菌菌株中发现并鉴定了一种名为Kapi 1的新的温带噬菌体。从老鼠消化道中分离出的大肠杆菌。我们将利用我们在细菌遗传学和包膜应激反应研究方面的专业知识，启动一项新的研究计划，研究噬菌体和细菌如何相互作用，影响微生物的适应性和应激适应。我们的工作将为未来控制和利用环境中的细菌、工业用途以及改善人类和动物健康的努力提供信息。