Characterizing Neuropeptides with Chiral Modifications

伊利诺伊大学厄巴纳-香槟分校的Jonathan Sweedler教授得到了分析和表面化学计划的支持，以分析神经肽中的手性翻译后修饰，即被认为可以生物激活肽的L到D异构化。 所研究的生物系统是Aaplasia californica的单个神经元。 有三种方法：仪器，酶和免疫学。 首先，手性分离方法将用于尝试拆分非对映体肽，其不同之处在于其中一种氨基酸的D/L异构化。 其次，将使用仅切割L-氨基酸的N-末端肽酶，然后通过基质辅助激光解吸电离质谱法（MALDI）分析片段。 第三种方法是尝试培养针对含有D-氨基酸的肽的抗体。 目标是发现新的D-氨基酸含有肽的神经功能。 本实验室的学生接受分析化学和神经生物学方面的培训。 大脑和神经系统中的信号传递在很大程度上是由大量的肽完成的，其中许多肽尚未被发现。 经过充分研究的Aaprosia蜗牛系统为研究人员提供了一个已经知道很多的模型系统。 该项目的成功将使人们更好地了解神经化学中的肽，以及阿尔茨海默氏症等神经疾病，并将有助于生物学和药学中其他问题的分析方法的进步。

Professor Jonathan Sweedler of the U of Ill Urbana-Champaign is supported by the Analytical and Surface Chemistry Program to analyze a chiral post-translational modification in neuropeptides, namely, an L to D isomerization thought to activate the peptide biologically. The biological system under study is the single neuron of Aplysia californica. There are three proposed approaches: instrumental, enzymatic and immunological. In the first, chiral separation methods will be used to try to resolve diastereomeric peptides that differ by D/L isomerization of one of the amino acids. Secondly, N-terminal peptidases that cleave only L-amino acids will be used followed by analysis of fragments by matrix-assisted laser desorption ionization mass spectrometry (MALDI). A third approach is to attempt to grow antibodies to peptides containing D-amino acids. The goal is to discover new D-amino acid containing peptides that function neurologically. Students in this laboratory are trained in analytical chemistry and neurobiology. Signaling in the brain and nervous system is accomplished to a large extent by a vast number of peptides, many as yet undiscovered. The well studied Aplysia snail system gives researchers one model system that a great deal is already known about. Success of this project will allow a better understanding of peptides in neurochemistry, as well as in neurological diseases such as Alzheimer's, and will also contribute to advances in analytical methods for other questions in biology and pharmacy.