Synthesis and Use of Chiral Beta-Deuterated Amino Acids for NMR Studies of Protein Structure

9723642柯利由现代核磁共振方法确定的蛋白质的结构指认，极大地方便了获得适当的区域和立体选择性标记的氨基酸，这些氨基酸可以并入蛋白质中。使用这些标记的氨基酸极大地提高了实验的灵敏度，并允许使用同位素编辑的核磁共振实验，这些实验可以提供否则难以获得的特定结构信息。对于通过核磁共振确定蛋白质的准确溶液结构来说，特别重要的是对氨基酸侧链共振的立体特异性指定。对这些指认有用的是通过用手性(-亚甲基)质子立体选择性地取代这些氨基酸的(-亚甲基)基团上的质子来获得这些氨基酸。此外，~(13)C弛豫速率的(-)效应也将促进C(碳的指认，特别是在大系统中。将开发一种通用的、通用的、廉价的方法来合成几乎所有带有手性(-亚甲基)质子的氨基酸，这种方法将以立体选择性的方式将其中一个手性质子用氚取代。这些方法还将允许以各种模式与15N或13C双重标记氨基酸，并且还可以容易地改装以立体专一性地提供天然氨基酸L-异构体。一旦获得，这些氨基酸将被用来通过核磁共振研究生物合成和蛋白质结构。蛋白质的功能取决于它们的结构。核磁共振波谱已成为确定蛋白质溶液结构的重要工具。蛋白质由不同的氨基酸组成，它们结合在一起构成整个蛋白质。如果用非放射性的、核磁共振可检测的同位素标记氨基酸，蛋白质的核磁共振研究就会变得更容易。该项目将开发合成这些特殊标记的氨基酸的一般方法。***

9723642 Curley The structure assignment of proteins as determined by modern NMR methods is greatly facilitated by access to appropriate regio- and stereoselectively labelled amino acids which can be incorporated into the proteins. Use of these labelled amino acids greatly increases experimental sensitivity and permits the use of isotope-edited NMR experiments which can provide specific structural information otherwise difficult to obtain. Of particular importance to assigning an accurate solution structure of a protein by NMR is stereospecific assignment of the amino acid side chain resonances. Useful for these assignments is access to amino acids with stereoselective substitution of deuteron for proton on the (-methylene groups of these amino acids with prochiral (-methylene protons. In addition, the effect of (-deuteration of the 13C relaxation rate will also facilitate C(carbon assignments, especially in large systems. A generalized, versatile, inexpensive method will be developed for the synthesis of virtually all the amino acids with prochiral (-methylene protons in a manner which will stereoselectively replace one of the prochiral protons with deuteron. These methods will also permit double labelling of the amino acid with 15N or 13C in a variety of patterns and can also be readily adapted to provide the natural amino acid L-isomer stereospecifically. Once obtained, these amino acids will be used to study biosynthesis and protein structure by NMR The function of proteins is dependent on their structure. Nuclear magnetic resonance (NMR) spectroscopy has become an important tool for determining the structure of proteins in solution. Proteins are composed of different amino acid building blocks which are bound together to make up the entire protein. The NMR study of proteins is made easier if the amino acids are labelled with nonradioactive, NMR-detectable isotopes. This project will develop general methods for the synthesis of these specially labelled amino acids. ***