CAREER: Bacterial heterogeneity in stress survival

职业：压力生存中的细菌异质性

• 批准号: 2240028
• 负责人: Nicholas Butzin
• 金额: $ 130万
• 依托单位: South Dakota State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-04-01 至 2028-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2240028&HistoricalAwards=false
• 关键词: CAREER; Bacterial; heterogeneity; stress; survival

Bacterial persisters have an incredible ability to survive stress and are a major cause of recurrent bacterial infections, failures in antibiotic drug therapy, and evolution of antibiotic resistance. Most cells in a bacterial population die when exposed to a major stress, such as antibiotics, but a small fraction of cells survive for a long time. These survivors, also known as persisters, appear to arise as a result of variability in cell behaviors across the population. The goal of this project is to discover the mechanisms that allow the formation, maintenance, and survival of bacterial persisters and thus to help understand key features of bacterial survival. The work will involve student researchers, including those from underrepresented groups, who will participate in synthetic biology research experiences as part of the project's educational objectives. In addition, the project will provide professional development workshops for K-12 science teachers to enhance their ability to integrate synthetic biology modules into their classrooms. The overall goal of this research is to identify the mechanism that enables some bacterial cells to survive after exposure to stress. One hypothesis to be tested is that survival depends on establishment of some type of epigenetically-determined ‘memory’ of stress that results in higher persister numbers after exposure to the stress. To understand the regulatory processes that enable persisters to survive long-term, lethal stress, the project will use a suite of experimental approaches, such as fluorescence microscopy, microfluidics, and a modified Luria–Delbrück fluctuation test, with synthetic biology and quantitative modeling. In addition, transcriptional analysis, single-cell experiments, and high-throughput techniques will be used to quantify epigenetic patterns in bacteria. The research will produce a quantitative framework for understanding the mechanism responsible for the phenotypic heterogeneity thought to serve as an inherent survival strategy of bacteria. This work will impact fundamental knowledge of how bacteria survive sudden lethal stress and how they deal with harsh environmental fluctuations. The results are expected to offer new insights into the fundamental molecular mechanisms of how cells revive from lethal stress.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.

细菌持久性具有不可思议的能力，可以使胁迫生存，并且是复发细菌感染，抗生素药物治疗失败以及抗生素耐药性的进化的主要原因。细菌群体中的大多数细胞在暴露于主要胁迫（例如抗生素）时死亡，但是很少的细胞长期存活。这些生存（也称为持久者）似乎是由于人群中细胞行为的变化而产生的。该项目的目的是发现允许细菌持久形成，维持和存活的机制，从而帮助理解细菌存活的关键特征。这项工作将涉及学生研究人员，包括来自代表性不足的团体的研究人员，他们将作为该项目的教育目标的一部分参加合成生物学研究经验。此外，该项目将为K-12科学教师提供专业发展研讨会，以增强其将合成生物学模块整合到课堂中的能力。这项研究的总体目标是确定使某些细菌细胞在承受压力后生存的机制。一个要检验的假设是，生存取决于建立某种表观遗传确定的压力的“记忆”，这会导致暴露于压力后较高的持久数量。为了理解使持久者能够长期生存的调节过程，该项目将使用一系列实验方法，例如荧光显微镜，微流体和修饰的Luria-Delbrück波动检验，并通过合成生物学和定量模型进行。此外，转录分析，单细胞实验和高通量技术将用于量化细菌中的表观遗传模式。这项研究将产生一个定量框架，以理解负责表型异质性的机制，认为这是细菌的继承生存策略。这项工作将影响细菌如何生存突然致命的压力以及如何应对有害环境波动的基本知识。预计该结果将为细胞如何从致命压力中复活的基本分子机制提供新的见解。该奖项反映了NSF的法定任务，并使用基金会的知识分子和更广泛的影响评估标准，认为值得通过评估来支持。