Antibiotic resistance gene propagation: in situ rates and networks of horizontal gene transfer in wastewater

抗生素抗性基因传播：废水中水平基因转移的原位速率和网络

• 批准号: 1805901
• 负责人: Lauren Stadler
• 金额: $ 33万
• 依托单位: William Marsh Rice University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-08-15 至 2022-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1805901&HistoricalAwards=false
• 关键词: Antibiotic; resistance; gene; propagation; situ

A major challenge to combating the global health crisis of antibacterial resistance is that antibiotic resistance genes (ARGs) can be shared among bacteria through a process called horizontal gene transfer (HGT). ARGs are present in wastewater, and there is little understanding of ARG health impacts potentially conveyed by recycling wastewater. Little is known regarding the conditions that result in HGT of ARGs from environmental bacteria such as those used to treat wastewater and pathogenic bacteria found in clinical infections. The goals of this project are to decipher how pathogens acquire ARGs from environmental bacteria present in water and wastewater systems and to understand how ARGs are propagated in water and wastewater microbial communities. This research will develop biosensors to monitor HGT of ARGs to understand how simple operational parameters in a wastewater treatment plant impact the reduction or proliferation of ARGs. If successful, the results of this project will identify methods of antibiotic resistance transfer in the environment and identify ways to halt this transfer during water treatment processes, protecting public health and the Nation's water supply.Understanding the controls over horizontal gene transfer (HGT) in microbial communities found in the environment would impart an unprecedented ability to manage the growing threat of antibiotic resistance. While a variety of technologies are available for obtaining static snapshots of bacteria that have acquired antibiotic resistance genes (ARGs) through HGT, these existing approaches do not provide dynamic information on the pathways and rates of gene flow within complex communities that experience a changing environment. These approaches also cannot easily differentiate between living and dead bacteria. Two emerging tools will be leveraged to obtain this information: (1) gas-reporting biosensors that report on in situ conjugation events; and (2) a high-throughput, culture-independent method for determining the host-range of ARGs in a mixed community. These tools will be applied in bioreactors treating domestic wastewater to better understand how operational controls impact ARG propagation rates and host range. The objectives of this research are to (1) develop biosensors that report on HGT in situ by coupling the synthesis of an enzyme that produces a rare volatile gas to broad-range plasmid transfer; (2) use these tools in bench-scale wastewater bioreactors to monitor HGT rates across a community under various reactor conditions; and (3) characterize the host range of the engineered plasmids and of a suite of environmentally-relevant ARGs under different bioreactor operational conditions. The results of this research will advance the knowledge of the mechanisms that govern HGT of ARGs in wastewater treatment and water reuse systems that will inform management strategies to protect human health.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.

对抗抗生素耐药性的全球健康危机的一个主要挑战是抗生素耐药性基因（ARG）可以通过一种称为水平基因转移（HGT）的过程在细菌之间共享。ARG存在于废水中，人们对回收废水可能带来的ARG健康影响知之甚少。关于导致来自环境细菌的ARG HGT的条件知之甚少，例如用于处理废水的细菌和临床感染中发现的病原菌。该项目的目标是破译病原体如何从水和废水系统中存在的环境细菌中获得ARGs，并了解ARGs如何在水和废水微生物群落中繁殖。这项研究将开发生物传感器来监测ARGs的HGT，以了解废水处理厂的简单操作参数如何影响ARGs的减少或增殖。如果成功的话，该项目的结果将确定环境中抗生素耐药性转移的方法，并确定在水处理过程中阻止这种转移的方法，保护公众健康和国家的供水。了解环境中发现的微生物群落中水平基因转移（HGT）的控制将赋予前所未有的能力来管理日益增长的抗生素耐药性威胁。虽然各种技术可用于获得通过HGT获得抗生素抗性基因（ARG）的细菌的静态快照，但这些现有方法不能提供有关经历不断变化的环境的复杂社区内基因流动的途径和速率的动态信息。这些方法也不能很容易地区分活细菌和死细菌。将利用两种新兴工具来获得这一信息：（1）报告原位缀合事件的气体报告生物传感器;（2）用于确定混合群落中ARG宿主范围的高通量、不依赖培养的方法。这些工具将应用于处理生活废水的生物反应器，以更好地了解操作控制如何影响ARG繁殖率和宿主范围。本研究的目的是（1）通过将产生稀有挥发性气体的酶的合成与大范围质粒转移偶联来开发原位报告HGT的生物传感器;（2）在实验室规模的废水生物反应器中使用这些工具来监测不同反应器条件下整个社区的HGT速率;和（3）在不同生物反应器操作条件下表征工程质粒和一套环境相关ARG的宿主范围。这项研究的结果将促进对废水处理和水回用系统中ARG HGT管理机制的了解，这将为保护人类健康的管理战略提供信息。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。