OPTICAL ROTATORY POWER OF BIOPOLYMERS

生物聚合物的旋光能力

• 批准号: 3268177
• 负责人: JEN T YANG
• 金额: $ 14.71万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 1979
• 资助国家: 美国
• 起止时间: 1979-05-01 至 1989-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3268177
• 关键词: acetylcholinesterase; bacteriorhodopsins; bungarotoxins; chemical aggregate; chemical structure function; circular dichroism; conformation; copper; detergents; hydropathy; ligands; liposomes; membrane lipids; metalloproteins; optical rotation; phospholipids; superoxide dismutase; synthetic peptide; thermodynamics

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.

长期目标是了解结构-功能 通过生物物理学研究确定了几种生物聚合物之间的关系。 的 溶液中的几种多肽和蛋白质的构象将是 通过圆二色性与其他物理化学方法一起研究。 我们的工作假设是多肽在表面活性剂中的构象 和脂质溶液是由它们的一级结构决定的， 在两亲性多肽（例如蜂毒肽的片段和 细菌视紫红质）和强疏水性多肽（例如信号肽 肽）。 两个新的项目启动：一个是两个主要的蛋白质， 胆碱能神经传递和其他对金属离子环肽 配合物 两个不对称的构象和酶活性 （可溶性）和球状（膜结合）形式的乙酰胆碱酯酶， 乙酰胆碱受体及其亚单位（α 2 β γ δ） 将研究加州鱼雷。 构象变化，如果 在激动剂和拮抗剂的存在下， 测定 脂质中重组受体和酶的构象 将通过各种物理方法研究囊泡。 二是 一系列二酮哌嗪如c（His）2和c（Cys-Met），以及后来的， 将合成环状六肽。 的配合物 这些具有金属离子如Cu、Co、Ni、Mn和Fe的化合物模拟了 几种金属蛋白如Cu/Zn超氧化物歧化酶的活性位点， 质体蓝素和天青蛋白。 构象和可能的催化活性 这些复合物将与那些 相应的金属蛋白。 选择蛋白质和模型化合物， 因为它们的生物学意义和健康相关的重要性。