Design and Oligomerization of Uniquely Folded Supersecondary Structural Motifs

在有机和大分子化学项目的支持下，马萨诸塞州理工学院化学系的Barbara Imperiali教授正在研究"迷你蛋白质"基序的结构、缔合性质和功能。含有二硫键的29个残基的微型基序将被合理地设计为无二硫键的基序，并且用于"进化" 23个和29个残基基的生物学策略将被用于开发仅包括20个编码的氨基酸的微型基序，而不是依赖于目前用作转角稳定剂的一个或两个D-氨基酸。新的方法，包括使用荧光报告基团和具有溶剂化显色性质的氨基酸，将被实施，以允许发现具有离散的四级结构的肽低聚物。最后，Imperiali教授将探讨这些微型基序在分子识别和传感小分子（如荧光有机物种和荧光标记的单糖和二糖）中的可能功能。蛋白质（多肽）由相互连接的氨基酸长链组成，发挥着无数的生物化学作用。它们的特定功能严重依赖于多肽链所采用的三维结构，但负责蛋白质折叠的因素仍然不完全了解。通过设计、合成和研究小多肽，马萨诸塞州理工学院化学系的Barbara Imperiali教授在有机和大分子化学项目的支持下，阐明了形成特定蛋白质折叠基序的因素。她的研究还探索了这些“迷你基序”可以作为支架的可能性，以允许识别和传感小有机分子，包括糖，从而在更长的时间内设计基于肽的化学传感剂。

With the support of the Organic and Macromolecular Chemistry Program, Professor Barbara Imperiali, of the Department of Chemistry at the Massachusetts Institute of Technology, is studying the structure, association properties, and function of "mini-protein" motifs. A 29-residue mini-motif containing a disulfide link will be rationally designed to a disulfide-free motif, and a biological strategy for "evolving" 23- and 29-residue motifs will be used to develop mini-motifs including only the 20 encoded amino acids, rather than relying on one or two D-amino acids currently used as turn stabilizing agents. New methods, including the use of fluorescent reporter groups and amino acids with solvatochromic properties, will be implemented to permit the discovery of peptide oligomers with discrete quaternary structure. Finally, Professor Imperiali will explore the possible function of these mini-motifs in the molecular recognition and sensing of small molecules such as fluorescent organic species and fluorescently labeled mono- and disaccharides.Proteins (polypeptides), comprised of long chains of interconnected amino acids, play myriad biochemical roles. Their specific function is critically dependent on the three dimensional structure adopted by the polypeptide chain, yet the factors responsible for protein folding are still at best incompletely understood. Through the design, synthesis, and study of small polypeptides, Professor Barbara Imperiali, of the Department of Chemistry at the Massachusetts Institute of Technology, with the support of the Organic and Macromolecular Chemistry Program, is shedding light on the factors responsible for the formation of particular protein folding motifs. Her studies also explore the possibility that these "mini-motifs" could serve as scaffolds to permit the recognition and sensing of small organic molecules, including sugars, leading in the longer term to the design of peptide-based chemosensing agents.