RUI: Acid and Base Stress in Escherichia Coli

RUI：大肠杆菌中的酸和碱应激

• 批准号: 1050080
• 负责人: Joan Slonczewski
• 金额: $ 45.3万
• 依托单位: Kenyon College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-01-01 至 2014-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1050080&HistoricalAwards=false
• 关键词: RUI; Acid; Base; Stress; Escherichia

Acid and base affect bacterial growth and survival in soil and aquatic environments, impacting soil productivity and fisheries. In the human host, acid and base induce multidrug resistance genes. In the fermentation industry, pH (a measure of the acidity or alkalinity of a solution) plays critical roles in growth and production. For example, pH regulation of hydrogenase enzymes affects the biological production of hydrogen fuel. In industrial processes, bacteria often form biofilms in which the pH is decreased, accelerating corrosion; thus, acid stress response amplifies the role of biofilms in equipment deterioration. The proposed project addresses these questions: (1) How is pH regulated in single cells versus biofilms? (2) How do multidrug efflux pumps impact bacterial survival in extreme acid or base? (3) What novel components of acid survival and base stress are revealed at low oxygen? To address these questions, bacterial cell pH will be measured using fluorescence microscopy. The export of acidic products from drug efflux pumps will be measured. Acid and base stress will be tested during bacterial growth in low oxygen.Broader Impacts. This Research at Undergraduate Institutions Award will contribute to the nation's human resources by continuing an innovative research program run by undergraduates. Undergraduates are recruited in their first year to start in the lab, learning basic techniques while working with more advanced peers. Students then write their own mini-proposals, design and conduct the experiments, and draft the manuscript for publication. Most undergraduates attracted to work on the current project decide to pursue careers in science. In the wider community, the PI assists middle-school teachers and conducts teacher workshops on hands-on science education.

酸和碱影响土壤和水生环境中的细菌生长和存活，影响土壤生产力和渔业。在人类宿主中，酸和碱诱导多药耐药基因。在发酵工业中，pH值（溶液酸度或碱度的量度）在生长和生产中起着关键作用。例如，氢化酶的pH调节影响氢燃料的生物生产。在工业过程中，细菌经常形成生物膜，其中pH值降低，加速腐蚀;因此，酸应激反应放大了生物膜在设备劣化中的作用。该项目解决了以下问题：（1）单细胞与生物膜中的pH值是如何调节的？(2)多药外排泵如何影响细菌在极端酸或碱中的存活？(3)在低氧条件下，酸存活和碱胁迫的新成分是什么？为了解决这些问题，将使用荧光显微镜测量细菌细胞pH值。将测量来自药物外排泵的酸性产物的输出。细菌在低氧条件下生长期间将测试酸和碱胁迫。这个研究在本科院校奖将有助于国家的人力资源，继续由本科生运行的创新研究计划。本科生在第一年被招募到实验室开始，学习基本技术，同时与更先进的同行合作。然后，学生们写自己的迷你提案，设计和进行实验，并起草手稿出版。大多数本科生被吸引到目前的项目工作决定追求科学事业。在更广泛的社区中，PI协助中学教师，并举办关于实践科学教育的教师讲习班。