PHYSICAL CHEMISTRY OF BIOLOGICAL MACROMOLECULES

这个项目的目的是研究一种广泛的 各种生物大分子，目的是将它们相互关联 性质与大分子的结构和功能有关。这个 重点放在这些物质相互作用的热力学上。 大分子以及它们的分子大小和形状。分析性 主要研究内容为超速离心法和数学模型法 使用的技术。 纤维蛋白原与其他相关蛋白相互作用的研究 血液凝结和纤溶作用仍在继续。目前正在进行的研究 这一领域的研究进展涉及纤维蛋白原与血浆的关系 和血小板XIII及纤溶酶原与D的相关性 和纤维蛋白原的E片段。 对还原蓖麻毒素A链和B链相互作用的研究表明 AB复合体的形成是可逆的，温度 这个反应的依赖性表明它似乎是熵的。 驱动，这表明A之间有很强的疏水相互作用 和B链，即使在没有二硫键的情况下也是如此。细胞毒性 研究表明，还原的蓖麻毒素比天然的蓖麻毒素毒性更大。 浓度，表明链之间的二硫键是 不是生物活动所必需的。 EHS中硫酸肝素蛋白多糖的大、小两种形式 用电子显微镜和电子显微镜对肿瘤基底膜进行了研究。 分析超速离心法。这些研究表明，这些 蛋白多糖在肝素的数量和大小上表现出相似之处 硫酸盐侧链，但蛋白质核心的长度不同。

The purpose of this project is to study the physical properties of a wide variety of biological macromolecules with the goal of correlating these properties to the structure and function of the macromolecules. The emphasis is on the thermodynamics of the interactions of these macromolecules and on their molecular size and shape. Analytical ultracentrifugation and mathematical modeling are the principal research techniques used. Studies on the association of fibrinogen with other proteins involved in blood clotting and fibrinolysis have been continued. Studies currently in progess in this area deal with the association of fibrinogen with plasma and platelet Factor XIII and with the association of plasminogen with the D and E fragments of fibrinogen. Studies on the association of the A and B chains of reduced ricin indicate that the formation of the AB cmplex is reversible and that the temperature dependence of this reaction indicates that it appears to be entropically driven, suggesting that there is a strong hydrophobic interaction between A and B chains even in the absence of the disulfide bond. Cell toxicity studies indicate that reduced ricin is more toxic than native ricin at high concentrations, indicating that the disulfide bond between the chains is not necessary for biologcial activity. The small and large forms of heparin sulfate proteoglycan isolated from EHS tumor basement membrane have been studied by electron microscopy and by analytical ultracentrifugation. These studies indicate that these proteoglycans show similarities in the number and size of the heparin sulfate side chains but differ in the length of the protein core.