Selenium Homeostasis in Stenotrophomonas Maltophilia ORO2 and E. coli

嗜麦芽寡养单胞菌 ORO2 和大肠杆菌中的硒稳态

• 批准号: 0542178
• 负责人: Jonathan Caguiat
• 金额: $ 14.98万
• 依托单位: Youngstown State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-04-15 至 2009-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0542178&HistoricalAwards=false
• 关键词: Selenium; Homeostasis; Stenotrophomonas; Maltophilia; ORO2

Stenotrophomonas maltophilia ORO2 (S. maltophilia O2) was isolated from a heavy metal contaminated stream in Oak Ridge, TN. This strain demonstrated the ability to precipitate selenite, an inorganic form of selenium. Selenium is an essential trace element for all living organisms, but exposure to high concentrations in the form of selenite can be lethal. This research will focus on the ability of selenite resistant bacteria to process selenium when exposed to toxic levels of selenite. A S. maltophilia O2 gene, which may be involved in selenite resistance, was transferred to and conferred selenite resistance in a common laboratory strain of Escherichia coli (E. coli). Mechanisms of resistance will be studied using proteomics to examine the total number of proteins expressed under certain growth conditions. Selenite resistant strains of S. maltophilia O2 and E. coli will be grown in two different cultures, one with toxic levels of selenite and the other without selenite. Proteins from bacteria grown under each condition will be isolated and separated using 2-dimensional gel electrophoresis. The intensity of spots in the two gels will show which proteins are more abundant in the presence of selenite than in its absence. The proteins in the spots will then be identified using a mass spectrometry technique. By identifying and studying proteins expressed in the presence of high selenite concentrations, it will be possible to understand selenium homeostasis (a balance of selenium intake with selenium detoxification) in bacteria. Results from this research may also provide insights into the role of selenium as an antioxidant.The broader educational impact of this project will be tremendous. This research will introduce underrepresented minority students in the Youngstown Early College (YEC) program (seventy-three percent of the students in this program are underrepresented minorities) to a career in science and contribute to the educational focus of the Youngstown 2010, a plan to revive the arts, health care, government, and education of the city. The YEC is a program in which the Youngstown city school district collaborates with Youngstown State University to provide underprivileged high school students with the opportunity to receive their high school education in a university setting. While these students have access to some of the college courses on campus, they do not have the opportunity to work in research laboratories. YEC students will be invited to participate in the research project on selenite resistance.

嗜麦芽寡养单胞菌ORO2 （S. maltophilia O2）是从田纳西州橡树岭重金属污染的河流中分离出来的。该菌株具有沉淀亚硒酸盐（硒的无机形式）的能力。硒是所有生物必需的微量元素，但接触高浓度的亚硒酸盐可能是致命的。这项研究将集中于亚硒酸盐抗性细菌在暴露于有毒水平的亚硒酸盐时处理硒的能力。一种可能参与亚硒酸盐抗性的嗜麦芽葡萄球菌O2基因被转移到一种常见的实验室菌株大肠杆菌（E. coli）中并赋予亚硒酸盐抗性。抗性机制将利用蛋白质组学来研究在特定生长条件下表达的蛋白质总数。耐亚硒酸盐菌株嗜麦芽杆菌O2和大肠杆菌将在两种不同的培养物中生长，一种亚硒酸盐有毒，另一种不含亚硒酸盐。在每种条件下生长的细菌中的蛋白质将用二维凝胶电泳分离。两种凝胶中的斑点强度将显示出在亚硒酸盐存在时哪种蛋白质比在亚硒酸盐不存在时更丰富。然后用质谱技术鉴定斑点上的蛋白质。通过鉴定和研究在高亚硒酸盐浓度下表达的蛋白质，将有可能了解细菌中的硒稳态（硒摄入与硒解毒的平衡）。这项研究的结果也可能为硒作为抗氧化剂的作用提供见解。这个项目对教育的广泛影响将是巨大的。这项研究将介绍杨斯敦早期学院（YEC）项目中未被充分代表的少数民族学生（该项目中73%的学生是未被充分代表的少数民族）从事科学事业，并为杨斯敦2010年的教育重点做出贡献，这是一项振兴城市艺术、医疗保健、政府和教育的计划。YEC是扬斯敦市学区与扬斯敦州立大学合作的一个项目，旨在为贫困高中学生提供在大学环境中接受高中教育的机会。虽然这些学生可以在校园里学习一些大学课程，但他们没有机会在研究实验室工作。邀请YEC学生参与亚硒酸盐抗性的研究项目。