MRI: Acquisition of a 300 Megahertz Broadband Nuclear Magnetic Resonance (NMR) for Undergraduate Research and Research Training at Loras College

洛拉斯学院的大卫·斯佩克哈德博士获得了一笔赠款，用于购买一台高场核磁共振(核磁共振)光谱仪。斯佩克哈德博士和洛拉斯的学生将使用核磁共振研究用于探测酶活性部位的分子的三维结构。酶是一种大型蛋白质，可以催化(加速)活细胞中发生的化学反应。每种酶都有一个小口袋或裂隙，称为活性部位，催化发生的地方。这个部位的形状决定了它们所能加速的反应类型。探针分子就像一只手在手套里一样适合这个部位。核磁共振被用来确定最适合的探针的确切形状，从而揭示位置的形状。在一种情况下，核磁共振可以用来评估位置与探针接触的位置，从而获得更好的位置图像。为这项研究选择的酶都参与细胞能量的产生，并且都与含有化合物三磷酸腺苷(ATP)的磷酸盐结合。每种酶还可以结合其他含磷化合物，这些化合物的位置形状是独一无二的。例子包括与PEP的丙酮酸激酶结合的CEPA，以及与肌酸激酶结合的磷酸肌酸。在细胞中，一种金属离子(镁)帮助磷酸化合物与酶结合。用钴代替镁创造了一种探测分子，它能保持足够长的时间进行研究。核磁共振被用来确定探针分子中的哪些原子与钴相连。核磁共振还将有助于甘油激酶位点的研究。在这种情况下，探测器将是富含碳13的三磷酸腺苷。MNR将报告从探针中的碳13原子和磷31原子到酶位置上取代镁的锰原子的距离。这些距离可以用来创建一张很好的甘油激酶位置图。小分子与大生物分子的相互作用在许多生物化学领域是重要的。研究几种酶的形状要求将有助于确定酶是如何具有如此强大和选择性的催化剂的能力的。这些方法可以应用于药物受体的相互作用，以显示新药如何与细胞内的生物分子相互作用，以及如何设计出更有效和副作用更少的药物。这些方法在农业化学中也很有用，有助于生产更好的化肥和杀虫剂。该提案的一个重要特点是为本科生提供了在他们的研究中使用高场核磁共振的机会。这一机会将显著改善洛拉斯学院学生的教育体验，因为MNR技术在他们未来的医学、生物技术和化学研究职业生涯中非常重要。

A grant has been awarded to Dr. David Speckhard at Loras College to purchase a high field Nuclear Magnetic Resonance (NMR) spectrometer. Dr. Speckhard and Loras students will use the NMR to study the three dimensional structure of molecules that are used to probe the active sites of enzymes. Enzymes are large proteins that catalyze (accelerate) the chemical reactions that occur in living cells. Each enzyme has a small pocket or cleft, called the active site, where catalysis occurs. The shape of this site determines what kind of reactions they enzyme can accelerate. Probe molecules fit in the site like a hand in a glove. The NMR is used to determine the exact shape of those probes that fit best, thereby revealing the shape of the site. In one case the NMR can be used to evaluate where the site touches the probe giving an even better picture of the site.The enzymes chosen for this study are all involved in cellular energy production, and all bind the phosphate containing compound Adenosine Triphosphate (ATP). Each enzyme can also bind other phosphate contatining compounds unique to their site shape. Examples include pyruvate kinase binding CEPA of PEP, and creatine kinase binding phosphocreatine. In the cell, a metal ion (magnesium) helps the phosphate compounds bind in the enzyme site. Substituting cobalt for magnesium creates a probe molecule that keeps its shpae long enough to study. The NMR is used to detemine which atoms of the probe mjolucule are connected to the cobalt. The NMR will also aid in the study of the glycerokinase site. In this case the probe will be carbon 13 enriched ATP. The MNR will report the distances from the carbon 13 atoms and phosphorous 31 atom in the probe to a manganese atom substituted for magnesium in the enzyme site. These distances can be used to create a good map of the glycerokinase site.The interaction of small molecules with large biomolecules is important in many areas of biochemistry. Studying the shape requirements in several kinase enzymes will help determine how enzymes have the ability to be such powerful and selective catalysts. These methods can be applied to drug receptor interactions to show how new medicines interact with biomolecules inside cells and how they may be designed to be more effective and have fewer side effects. These methods are also useful in agricultural chemistry to help produce better fertilizers and pesticides. A significant feature of the proposal is the opportunity provided to undergraduates to use the high field NMR in their research. This opportunity will significantly improve the educational experience for Loras College students since MNR techniques are so important in their future careers in medicine, biotechnology and chemical research.