ENZYMES OF THE PROSTAGLANDIN CASCADE

镰状细胞性贫血的病理表现是 HbS聚合成变形形状的长纤维 红血球。由此产生的异常形状和增加 僵硬的红血球阻碍了血液流经 导致血管闭塞并发症的毛细血管 以镰状细胞性贫血为特征。脑血管疾病是一种 儿童常见的灾难性并发症之一 患有镰状细胞性贫血。 我们已经开始对结构进行长期调查，并 前列腺素合成级联酶的功能。多数 这些酶中的一种是膜结合酶，因此需要 特殊处理，为他们的生物物理分析做准备。因为我们 已经开发出使膜蛋白结晶的方法，他们 现在可以对X-射线衍射分析进行修正。使用X- 射线结晶学、电子顺磁共振、UV-Vis 吸收光谱和氟-核磁共振，我们打算研究 参与合成血管调节剂的酶 前列腺素。我们现在正在研究酶-药物和酶- 前列腺素H合成酶底物类似物(环- 加氧酶)，在溶液和晶体中都有。的产品 前列腺素H合成酶，即PGH1和PGH2，可作为 前列腺素类化合物的合成及其对血小板攻击的影响 血管扩张。我们打算使用我们为其开发的方法 前列腺素合成酶的纯化、结晶及活性研究 前列腺素H-前列腺素E异构酶和前列腺素I2合酶的调查研究 它们合成了强大的血管扩张剂和血小板抑制剂 聚合。我们的长期目标是阐明 底物、产物和缓蚀剂与1)的结合机理 更好地理解催化过程中发生的分子事件 和2)提供必要的结构信息 设计控制特定前列腺素合成的药物。 有特定的合成的抑制物或激活剂 前列腺素可促进合理药物治疗的发展 适用于镰状细胞性贫血等血管闭塞疾病。

The pathological manifestations of sickle cell anemia arises from the polymerization of HbS into long fibers which distort the shape of the red blood cell. The resulting abnormal shape and increased rigidity of the red blood cells impedes blood flow through the capillaries causing the vasoocclusive complications that characterize sickle cell anemia. Cerebral vascular disease is a common and one of many catastrophic complications in children suffering from sickle cell anemia. We have started a long-term investigation into the structure and functional of enzymes in the prostaglandin synthesis cascade. Most of these enzymes are membrane bound enzymes and thus require special handing to prepare them for biophysical analysis. As we have developed methods for crystallizing membrane proteins, they now can be made amendable to X-ray diffraction analysis. Using X- ray crystallography, electron paramagnetic resonance, UV-Vis absorption spectroscopy and fluorine-NMR, we intend to study the enzymes that participate in the synthesis of vasoregulatory prostaglandins. We are now investigating enzyme-drug and enzyme- substrate analog complexes of prostagland H synthase (cyclo- oxygenase), both in solution and in crystals. The products of prostaglandin H synthase, PGH1 and PGH2, serve as precursors for synthesis of prostaglandins which affect platelet aggression and vasodilation. We intend to use the methods we have developed for the study prostaglandin synthase to purify, crystalize and investigate and investigate PGH-PGE isomerase and PGI2 synthase which synthesize powerful vasodilators and inhibitors of platelet aggregation. Our long term goal is to elucidate the structural mechanisms of substrate, product and inhibitor binding to 1) understand better the molecular events occurring during catalysis and 2) to provide the necessary structural information for the design of drugs to control the synthesis of specific prostaglandin. Having inhibitors or activators of the synthesis of specific prostaglandins could allow the development of rational drug therapy for vasoocclusive diseases like sickle cell anemia.