Sulfide Oxidation and Signaling

硫化物氧化和信号传导

• 批准号: 10360743
• 负责人: RUMA V BANERJEE
• 金额: $ 6.95万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10360743
• 关键词: Address; Affect; Allosteric Regulation; Binding; Biochemical; Biogenesis; Blood Vessels; Catabolism; Cells; Coupled; Crystallization; Cystathionine beta-Synthase; Cysteine; Cysteine Desulfhydrase; Defect; Dioxygenases; Disease; Electron Spin Resonance Spectroscopy; Electron Transport; Environment; Enzymes; Failure; Foundations; Health; Heme; Homeostasis; Human; Hydrogen Sulfide; Inflammation; Kinetics; Medical; Mitochondria; Mutation; Oxidoreductase; Pathway interactions; Patients; Physiological; Proteins; Quinones; Reaction; Regulation; Research; Research Support; S-Adenosylmethionine; Schedule; Scientist; Signal Transduction; Signaling Molecule; Sulfides; Sulfur; Sulfur Metabolism Pathway; Thiosulfate Sulfurtransferase; Training; Work; mutant; neuroregulation; oxidation; persulfides; potentiometric titration; sulfite oxidase; sulfurtransferase

Hydrogen sulfide (H2S), a signaling molecule that elicits profound physiological effects, is a product of mammalian sulfur metabolism and is synthesized at relatively high rates. H2S is biosynthesized by three enzymes in the sulfur network of which two, cystathionine beta- synthase (CBS) and gamma-cystathionase, reside in the cytoplasmic transsulfuration pathway while the third, mercaptopyruvate sulfurtransferase, is involved in cysteine catabolism. Since H2S is highly toxic, cells avoid its build-up by an efficient oxidation pathway that is housed in mitochondria and coupled to the energy-generating electron transfer chain. The constituent proteins include sulfide-quinone oxidoreductase, a persulfide dioxygenase, rhodanese and sulfite oxidase. While our studies on H2S biogenesis are supported by HL58784, our work on H2S oxidation and signaling are supported by GM130183. It is becoming increasing clear that the biosynthetic and catabolic pathways for H2S interact and modulate each other. Therefore, the sulfide research supported by HL58784, scheduled to expire this year, will be folded into and then formally included in the competitive renewal of GM130183. In this supplemental project, the following specific aims will be addressed to elucidate fundamental mechanisms of regulation of H2S synthesis by CBS in normal and disease states: i) elucidate the steady state kinetics of linker mutants in CBS in the canonical transsulfuration and non-canonical H2S-generating reactions, (ii) investigate perturbations in the heme environment by EPR spectroscopy and potentiometric titrations, (iii) assess the impact of the mutations on AdoMet-dependent modulation of CO and NO• binding to ferrous heme and on the cellular flux of sulfur, and (iv) crystallize the linker mutants that appear to be less prone to aggregation compared to wild-type CBS. The impact of the proposed studies will be fundamental (i.e. elucidating mechanims of allosteric regulation at the level of CBS and in the pathway), medical (i.e. understanding the biochemical basis of failure of disease- causing CBS mutations), and most importantly, training a URM scientist of high promise.

硫化氢（H2S）是一种引起深刻物理作用的信号分子，是 哺乳动物硫代谢的产物，并以相对较高的速率合成。 H2S 由硫网络中的三种酶生物合成，两个酶，两个胱淀粉β- 合成酶（CBS）和伽马囊杆菌酶，驻留在细胞质过性中 途径，而第三个胃丙氨酸硫酸盐硫酸盐转移酶则参与半胱氨酸 分解代谢。由于H2S是剧毒的，因此细胞避免通过有效的氧化堆积。 位于线粒体中并耦合到能量生成电子的途径 转移链。组成蛋白包括硫化物 - 喹酮氧化激酶，A 硫化二氧酶，罗丹尼和亚硫酸盐氧化酶。而我们对H2S的研究 生物发生由HL58784支持，我们在H2S氧化和信号传导方面的工作是 由GM130183支持。越来越清楚的是，生物合成和 H2S的分解代谢途径相互作用并相互调节。因此，硫化物 HL58784支持的研究计划于今年到期，将被折叠为 正式包含在GM130183的竞争更新中。在这个补充项目中， 将解决以下具体目标，以阐明 在正常和疾病状态下，CBS对H2S合成的调节：i）阐明稳定 CBS中连接器突变体的状态动力学在规范的反硫和非典型的动力学中 H2S生成反应，（ii）EPR研究血红素环境中的扰动 光谱和电位测量滴定，（iii）评估突变对 CO和NO的ADOMET依赖性调制•与亚铁血红素结合并在细胞上结合 硫的通量，（iv）结晶的接头突变体似乎不太容易 与野生型CBS相比，聚集。拟议的研究的影响将是 基本（即，在CBS和IN的水平上阐明变构调节的机制 途径），医学（即了解疾病失败的生化基础 - 引起CBS突变），最重要的是，训练了一个高希望的URM科学家。