RUI: Acid and Base Stress in Escherichia Coli

RUI：大肠杆菌中的酸和碱应激

• 批准号: 0234732
• 负责人: Joan Slonczewski
• 金额: $ 39.6万
• 依托单位: Kenyon College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-03-01 至 2007-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0234732&HistoricalAwards=false
• 关键词: RUI; Acid; Base; Stress; Escherichia

A grant has been awarded to Dr. Joan Slonczewski of Kenyon College to study acid and base stress in the bacterium, Escherichia coli, and to train undergraduate students in microbiological research. Bacteria make different proteins to help them survive extreme changes in pH, both in natural environments and within the human body. For this project (a continuation of MCB-9982437), a model of pH-regulated proteins has been developed. This model predicts that growth in acid leads E. coli to convert its food into alkaline fermentation products, and vice-versa. This model will be tested using two-dimensional gel electrophoresis to observe induction of metabolic enzymes that lead to different end products, which will, in turn, be identified by using high-performance liquid chromatography. In addition, the effects of various acidic and alkaline end products on bacterial metabolism will be studied. Acid and base regulation are important for bacteria to survive in soil and aquatic environments, as well as in the human intestine. E. coli is particularly interesting as a model organism whose genome has been sequenced, and as a "neutralophile," a species that can grow in either acid or base. Many mechanisms of food preservation, such as the use of weak acids benzoate and sorbate, depend on pH; yet increasingly food-borne pathogens are acid resistant. Revealing the mechanisms of response to pH change will help us to better understand its environmental effects, as well as the role of pH in food quality and preservation. Furthermore, understanding of pH and metabolism in bacterial cultures will contribute to biotechnology by helping improve growth conditions for bacterial production. Kenyon College emphasizes undergraduate education, and students will be involved in every aspect of this project as they are trained to perform research experiments in microbiology. Several undergraduates have already been attracted to work on the project, and they are encouraged to pursue careers in science.

凯尼恩学院的 Joan Slonczewski 博士获得了一笔资助，用于研究大肠杆菌的酸碱应激，并培训本科生进行微生物学研究。 细菌会产生不同的蛋白质，以帮助它们在自然环境和人体内的 pH 值极端变化中生存。 对于该项目（MCB-9982437 的延续），开发了 pH 调节蛋白的模型。 该模型预测，酸性环境中的生长会导致大肠杆菌将其食物转化为碱性发酵产物，反之亦然。该模型将使用二维凝胶电泳进行测试，以观察产生不同最终产物的代谢酶的诱导，而最终产物将通过使用高效液相色谱进行鉴定。 此外，还将研究各种酸性和碱性终产物对细菌代谢的影响。酸和碱调节对于细菌在土壤和水生环境以及人类肠道中的生存很重要。 大肠杆菌作为一种模式生物（其基因组已被测序）以及作为“嗜中性菌”（一种可以在酸或碱中生长的物种）特别有趣。 许多食品保存机制，例如使用弱酸苯甲酸盐和山梨酸盐，都取决于 pH 值；然而，越来越多的食源性病原体具有耐酸性。 揭示 pH 值变化的响应机制将有助于我们更好地了解其环境影响，以及 pH 值在食品质量和保存中的作用。 此外，对细菌培养物 pH 值和代谢的了解将有助于改善细菌生产的生长条件，从而为生物技术做出贡献。 凯尼恩学院强调本科教育，学生将参与该项目的各个方面，接受微生物学研究实验的培训。 一些本科生已经被吸引参与该项目，并鼓励他们从事科学事业。