PHYSICAL CHEMISTRY OF BIOLOGICAL MACROMOLECULES

这个项目的目的是研究一个广泛的物理性质 各种生物大分子，目的是将这些 大分子的结构和功能的性质。 的 重点是这些相互作用的热力学 大分子及其分子大小和形状。 分析 超浓缩和数学建模是主要的研究内容 使用的技术。 纤维蛋白原与其他蛋白质的相关性研究 凝血和纤维蛋白溶解仍在继续。 目前在 这一领域的研究涉及纤维蛋白原与血浆的结合 和血小板因子XIII，以及纤溶酶原与D 和纤维蛋白原的E片段。 对还原型蓖麻毒蛋白A链和B链结合的研究表明 AB复合物的形成是可逆的， 这种反应的依赖性表明，它似乎是熵 驱动，表明A之间存在强烈的疏水相互作用 和B链，即使在没有二硫键的情况下。 细胞毒性 研究表明，还原蓖麻毒素比天然蓖麻毒素毒性更高， 浓度，表明链之间的二硫键是 不是生物活动所必需的。 从EHS中分离的硫酸肝素蛋白聚糖的小和大形式 肿瘤基底膜已经通过电子显微镜和 分析超离心 这些研究表明， 蛋白聚糖在肝素的数量和大小上显示出相似性， 硫酸酯侧链，但不同的蛋白质核心的长度。

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.