OPTICAL ROTATORY POWER OF BIOPOLYMERS

长期的目标是理解结构-功能 通过生物物理研究筛选出几种生物聚合物之间的关系。这个 几种多肽和蛋白质在溶液中的构象将是 用圆二色谱结合其他物理化学方法进行研究。 我们的工作假设是表面活性物质中多肽的构象 而脂类溶液是由其一级结构决定的，会进一步 两亲性多肽(例如蜂毒素片段和 细菌视紫红质)和强疏水多肽(如信号 多肽)。启动了两个新的项目：一个是关于两种主要蛋白质的 胆碱能神经递质与金属离子环肽 复合体。两种不对称化合物的构象和酶活性 (可溶性)和球形(膜结合型)乙酰胆碱酯酶和 乙酰胆碱受体及其亚单位(Alpha2BetaGammaDelta) 将对来自加州鱼雷的研究。构象变化，如果 任何受体在激动剂和拮抗剂存在的情况下都会 下定决心。脂类中重组受体和酶的构象 囊泡将通过各种物理方法进行研究。第二，一个 例如c(His)2和c(Cys-Met)的一系列二酮基哌嗪，以及后来， 将合成环状六肽。的配位络合物 这些化合物与铜、钴、镍、锰和铁等金属离子模拟 铜/锌超氧化物歧化酶等几种金属蛋白的活性部位， 花青素和天青素。构象及其可能的催化活性 这些复合体的数量将与 相应的金属蛋白。选择了蛋白质和模型化合物 因为它们的生物学兴趣和与健康相关的重要性。

The long-range objective is to understand the structure-function relationship of a select few biopolymers by biophysical studies. The conformation of several polypeptides and proteins in solutions will be studied by circular dichroism together with other physicochemical methods. Our working hypothesis that the conformation of polypeptides in surfactant and lipid solutions is dictated by their primary structure will be further tested on amphipathic polypeptides (e.g. fragments of melittin and bacteriorhodopsin) and strongly hydrophobic polypeptides (e.g. signal peptides). Two new projects are initiated: one on two major proteins in cholinergic neurotransmission and the other on metal ion-cyclic peptide complexes. The conformation and enzymic activity of both the asymmetric (soluble) and globular (membrane-bound) forms of acetylcholinesterase and those of acetylcholine receptor and its subunits (Alpha2BetaGammaDelta) from Torpedo californica will be studied. The conformational changes, if any, of the receptor in the presence of agonists and antagonists will be determined. The conformation of reconstituted receptor and enzyme in lipid vesicles will be investigated by various physical methods. Second, a series of diketopiperazines such as c(His)2 and c(Cys-Met) and, later, cyclic hexapeptides will be synthesized. The coordination complexes of these compounds with metal ions such as Cu, Co, Ni, Mn and Fe mimick the active sites of several metalloproteins such as Cu/Zn superoxide dismutase, plastocyanin and azurin. The conformation and possible catalytic activity of these complexes will be related to and compared with those of the corresponding metalloproteins. The proteins and model compounds are chosen for their biological interest and health-related importance.