CAREER: CAS: Spectroscopic Investigations of Biological Tellurium and Selenium Detoxification

职业：CAS：生物碲和硒解毒的光谱研究

• 批准号: 1945661
• 负责人: Kelly Chacon
• 金额: $ 65万
• 依托单位: Reed College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-04-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1945661&HistoricalAwards=false
• 关键词: CAREER; CAS; Spectroscopic; Investigations; Biological

Tellurium (Te) is a toxic chemical element that poses a potential problem as an environmental contaminant as a result of its increased use in electronics, mining, batteries, and optics. A set of related tellurium ion resistence (TeR) proteins have been discovered in bacteria that are able to survive exposure to tellurium ions. With this award, the Chemistry of Life Processes Program in the Chemistry Division is funding Dr. Kelly N. Chacón from Reed College to use cutting edge light-based measurements to characterize the structural and biochemical properties of these bacterial TeR proteins. Understanding these proteins helps explain the relatively unknown biological reactions of tellurium, while exploring potential bioremediation methods for mining Te as a precious resource and detoxifying Te from contaminated soil. With this award, Dr. Chacón uses an assertive, multifaceted approach to increase the retention of students from underrepresented minority groups in the science, technology, engineering, and mathematical (STEM) disciplines. Her program increases inclusiveness in the STEM curriculum by emphasizing practices based on the principles of belongingness, capacity, and interest. She is hosting a yearly two-day conference and workshop that will bring graduate students of color and “other” (including diverse gender, low-social economic status and first generation groups) from across the country to Reed College to provide a broader view of science and scientists to students at this small liberal arts college. The discovery of tellurium-resistant (TeR) bacteria has led to the identification of a plasmid-encoded tellurium-resistance operon. There is a large gap in our knowledge of structure and function of the proteins expressed from the TeR genes. Furthermore, a paucity of information exists on the biochemical role of Te, despite its similarity to the other essential chalcogens (oxygen, sulfur, and selenium). The soluble anions tellurite (TeO3[2-]) and tellurate (TeO4[2-]) are xenobiotic compounds. Little is understood about the biochemistry of their toxicity and efflux. Bacteria must contend with exposure to non-essential toxic metals and expend energy toward rapid detoxification, and many have developed resistance to Te. Dr. Kelly N. Chacón will apply a combination of fundamental biochemistry, Selenium/Tellurium/Arsenic k-edge Extended X-ray Absorption Fine Structure (EXAFS), Cryo-electron microscopy (Cryo EM), and crystallography to characterize the essential TeR protein components and begin to fill in the blanks of fundamental Te biochemistry. In addition to giving new insight into chalcogen bioinorganic chemistry, understanding of the TeR proteins could potentially provide an intriguing Te bioremediation method for mining this precious resource and for detoxifying contaminated soil.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.

碲 (Te) 是一种有毒化学元素，由于其在电子、采矿、电池和光学领域的使用增加，已成为潜在的环境污染物问题。凭借这一奖项，化学部的生命过程化学项目正在资助里德学院的 Kelly N. Chacón 博士使用尖端的光基技术。通过测量来表征这些细菌 TeR 蛋白的结构和生化特性，了解这些蛋白有助于解释碲相对未知的生物反应，同时探索潜在的生物修复方法，将碲作为一种宝贵的资源进行开采，并从受污染的土壤中解毒。 Chacón 博士采用自信、多方面的方法来提高科学、技术、工程和数学 (STEM) 学科中代表性不足的少数群体学生的保留率。她的计划通过以下方式提高了 STEM 课程的包容性。强调基于归属感、能力和兴趣原则的实践，她每年举办一次为期两天的会议和研讨会，吸引有色人种和“其他”（包括不同性别、低社会经济地位和第一代群体）的研究生。 ）从全国各地来到里德学院，为这所小型文理学院的学生提供更广阔的科学和科学家视野。抗碲 (TeR) 细菌的发现导致了质粒编码的碲抗性的鉴定。我们对 TeR 基因表达的蛋白质的结构和功能的了解还存在很大差距，尽管 Te 与其他必需的硫属元素（氧、硫、可溶性阴离子亚碲酸根 (TeO3[2-]) 和碲酸根 (TeO4[2-]) 是异生化合物，对其毒性和生物化学性质了解甚少。细菌必须与非必需的有毒金属接触并消耗能量来快速解毒，并且许多细菌已经对碲产生了抵抗力。Kelly N. Chacón 博士将应用基本生物化学、硒/碲/砷 k-edge 的组合。扩展 X 射线吸收精细结构 (EXAFS)、冷冻电子显微镜 (Cryo EM) 和晶体学来表征基本的 TeR 蛋白成分并开始填补基础碲生物化学的空白除了提供对硫属元素生物无机化学的新见解外，对 TeR 蛋白的了解还可能为开采这种宝贵资源和解毒污染土壤提供一种有趣的碲生物修复方法。该奖项反映了 NSF 的法定规定。使命，并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，被认为值得支持。