The Study of Human Sulfuryl-Transfer Biology

在过去的半个世纪里，科学界已经编目了数百个信号小分子 通过磺化作用-信息素、药物、毒素、类固醇和多肽激素-有效地调节， 核受体和多巴胺受体配体…。在体内控制特定代谢物的磺化将允许 实验者以前所未有的精度探测和控制硫磺生物。我们最近的结构/功能 研究发现了一种强有力的策略，可以在体内防止单一化合物的磺化，而不会改变其 受体相互作用或抑制磺基转移酶(Sults)。许多疾病都与 个别代谢物的磺化。现在，我们第一次可以希望控制这些反应。我们 最近将该策略应用于一种雌激素受体激动剂，并将其体内疗效提高了约10,000倍。 我们将创造并在体内测试三种化合物(两种FDA批准的药物)的抗磺化衍生物 和一种内源性代谢物)，目的是提高我们预防某些帕金森氏症的能力 症状，控制避孕，调节甲状腺激素代谢。 SULT小分子变构的研究还处于起步阶段。人类的13种亚型中的11种， 它们中的每一个都在单独的代谢域中工作，含有一个或多个变构位点。代谢物- 与这些位点结合的变构，以及因此连接到异构体的途径，仍然未知。我们正在孤立 来自小分子人体组织和微生物区系的生物医学相关同工酶特异的同工酶变构 文库、生物活性筛选文库和电子代谢物文库。我们最近发现， 四氢生物蝶呤(THB)是儿茶酚胺类神经递质生物合成中的重要辅因子， 高度特异的SULT1A3变构抑制剂，可使神经递质失活。依赖于磺化的 人脑神经递质活动的调节建议将THB口袋作为一种新的 神经药理靶点。我们已经开发出一种方法，可以使配体结合部位的结构 根据配体的一维核磁共振波谱在几天内确定。我们正在使用这些结构，在 结合MD建模和蛋白质功能研究，了解变应素的分子基础 起作用的目的是创造能够抑制、激活和改变底物特异性的化合物 单独的sult亚型。利用这些方法，我们已经创造了第一个“人造”sult变构抑制剂。 -一种有效的、高选择性的SULT1A3抑制剂。 这个实验室中蛋白质功能研究的持续暗流是发现的源泉。我们是 现在揭示了混杂的，半位点的酶(例如，Sults)构象偶联了 它们彼此之间的不同反应--这一发现的意义超越了硫酰转移代谢。 此外，我们正在创建固体变构和催化的尖端模型，我们打算应用我们的 UDP-葡萄糖转移酶--另一种主要的II相酶系统--的专业知识。

During the last half century the scientific community has catalogued hundreds of signaling small molecules that are potently regulated via sulfonation — pheromones, drugs, toxins, steroid and peptide hormones, nuclear- and dopamine-receptor ligands… . Controlling sulfonation of specific metabolites in vivo would allow experimentalists to probe and control sulfur biology with unprecedented precision. Our recent structure/function studies resulted in a robust strategy for preventing sulfonation of a single compound in vivo without altering its receptor interactions or inhibiting sulfotransferases (SULTs). Numerous diseases have been causally linked to sulfonation of individual metabolites. Now, for the first time, we can hope to control these reactions. We recently applied the strategy to an estrogen-receptor agonist and increased its in vivo efficacy ~10,000-fold. We will create, and test in vivo, sulfonation-resistant derivatives of three compounds (two FDA-approved drugs and one endogenous metabolite) with the goal of improving our ability to prevent certain Parkinson's symptoms, control contraception, and regulate thyroid-hormone metabolism. The subject of SULT small-molecule allostery is in its infancy. Eleven of the thirteen human SULT isoforms, each of which operates in separate metabolic domain, harbor one or more allosteric sites. The metabolite- allosteres that bind these sites, and hence pathways linked to the isoforms, remain unknown. We are isolating biomedically relevant, isozyme specific SULT allosteres from small-molecule human-tissue and microbiota libraries, bioactive screening libraries, and in-silico metabolite libraries. We have recently discovered that tetrahydrobiopterin (THB), an essential cofactor in catecholamine neurotransmitter biosynthesis, is a potent, highly specific allosteric inhibitor of SULT1A3, which inactivates neurotransmitters. The sulfonation-dependent regulation of neurotransmitter activity in human brain recommends the THB pocket as a novel neuropharmacological target. We have developed methods that allow SULT ligand-binding site structures to be determined in a matter of days from a ligand's 1D NMR spectrum. We are using these structures, in conjunction with MD-modelling and protein-function studies, to understand the molecular basis of allostere function with the goal of creating compounds that can inhibit, activate and change the substrate specificities of individual SULT isoforms. Using these methods, we have created the first “man-made” SULT allosteric inhibitor — a potent, highly selective SULT1A3 inhibitor. The constant undercurrent of protein-function studies in this laboratory is a well-spring of discovery. We are now revealing that promiscuous, half-site enzymes (e.g., SULTs) conformationally couple the energetics of their disparate reactions to one another — a finding whose implications transcend sulfuryl-transfer metabolism. In addition, we are creating cutting-edge models of SULT allostery and catalysis, and we intend to apply our expertise to the UDP-glucosyltransferases — the other major phase II enzyme system.