Structure-function relationships in metalloenzymes with multiple redox-active centers

具有多个氧化还原活性中心的金属酶的结构-功能关系

• 批准号: 0843459
• 负责人: Arsenio Pacheco
• 金额: $ 41.05万
• 依托单位: University of Wisconsin-Milwaukee
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-01 至 2011-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0843459&HistoricalAwards=false
• 关键词: Structure; function; relationships; metalloenzymes; multiple

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). The Pacheco-Schmidt research groups are studying three proteins that allow certain bacteria to interconvert ammonia and nitrite. Without these proteins, such an interconversion would be too slow for bacterial survival. The primary aim of the project is to determine how the three proteins, which have broadly similar architectures, are tailored to shepherd the ammonia-nitrite interconversion preferentially in one direction or the other. Indirectly, the research will also supply a deeper understanding of nanoscale electronic device design, since the proteins are essentially conducting devices 5-10 nanometers wide. The proteins will be investigated using a variety of techniques, most notably time resolved X-ray crystallography (TRXRC), a relatively new method that allows one to make movies of molecules undergoing chemical reactions. The technique has enormous untapped potential, some of which will be uncovered during the project. Broader impacts. This project provides research opportunities to high school students and teachers, in addition to undergraduate and graduate students. It will also provide insight into a growing environmental problem: nitrogen cycle imbalance. Ammonia (a major component of fertilizer) and nitrite are two examples of reactive nitrogen; that is, nitrogen usable by many living organisms, as opposed to elemental nitrogen which makes up 89% of the air we breathe, but is directly usable by only a few bacteria. Together, elemental nitrogen and reactive nitrogen constitute the nitrogen cycle. Over the last 50 years the balance between the components of the nitrogen cycle has shifted significantly towards reactive nitrogen species, as more fertilizer was generated to produce food, and more recently biofuels. This shift is having many unintended negative consequences, which will have to be mitigated in the coming years. A better understanding of the processes by which ammonia and nitrite are interconverted may lead to the more efficient use of ammonia fertilizer, and thus help redress the nitrogen cycle imbalance. This award is co-funded by the Molecular and Cellular Biosciences Division and the Inorganic, Bioinorganic, and Organometallic Chemistry program of the Chemistry Division.

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。Pacheco-Schmidt研究小组正在研究三种蛋白质，这些蛋白质允许某些细菌将氨和亚硝酸盐相互转化。如果没有这些蛋白质，这种相互转化对细菌的生存来说太慢了。该项目的主要目的是确定这三种结构大致相似的蛋白质是如何定制的，以优先引导氨-亚硝酸盐在一个方向或另一个方向的相互转化。间接地，这项研究也将提供对纳米级电子设备设计的更深入的理解，因为蛋白质本质上是传导5-10纳米宽的设备。研究人员将使用多种技术来研究这些蛋白质，其中最引人注目的是时间分辨x射线晶体学（TRXRC），这是一种相对较新的方法，可以拍摄分子发生化学反应的电影。该技术具有巨大的未开发潜力，其中一些将在项目期间被发现。更广泛的影响。除了本科生和研究生外，该项目还为高中生和教师提供了研究机会。它还将提供对日益严重的环境问题的见解：氮循环失衡。氨（肥料的主要成分）和亚硝酸盐是活性氮的两个例子；也就是说，氮可以被许多生物利用，而不是构成我们呼吸的空气89%的元素氮，但只有少数细菌可以直接利用。元素氮和活性氮共同构成氮循环。在过去的50年里，随着越来越多的肥料被用于生产食物，以及最近的生物燃料，氮循环各组成部分之间的平衡已显著转向活性氮物种。这种转变正在产生许多意想不到的负面后果，这些后果必须在未来几年得到缓解。更好地了解氨和亚硝酸盐相互转化的过程可能会导致更有效地利用氨肥，从而有助于纠正氮循环不平衡。该奖项由分子和细胞生物科学部以及化学部的无机、生物无机和有机金属化学项目共同资助。