Coenzyme F420, helping mycobacteria find a niche in humans

项目总结 结核分枝杆菌是结核病的病原体，仍然是发病率和死亡率的重要原因。 全世界。肉芽肿内持续低氧状态是结核病的标志，导致潜伏感染。 以及限制现有疗法的应用。了解结核分枝杆菌如何支持其新陈代谢 在低氧条件下，并适应这些挑战，是消除潜伏结核病的关键。“解除武装”。 结核病通过消除其对肉芽肿应激诱导条件的耐受能力将提供一种可行的 潜伏性结核病的临床干预策略。 我们将探讨辅酶F420在结核分枝杆菌的生理和发病机制中的作用。F420是 一种脱氮黄素，在广泛的氢化物转移反应中充当载体。越来越多的证据表明 结核分枝杆菌广泛使用这种辅因子，其低氧化还原潜力被认为使其在缺氧中起关键作用 坚持不懈。分枝杆菌中似乎存在依赖于F420的机制，用于预防 氧化和亚硝化应激，但F420对结核分枝杆菌代谢和持久性的贡献 目前仍不清楚。该项目的最终目标是调查F420如何促进结核分枝杆菌的存活。 在低氧条件下肉芽肿内，阐明其在持久性中的作用。我们已经设计了一个完整的 使用遗传学、代谢组学、动物感染模型和蛋白质生物化学工具的实验方法 确定F420如何帮助结核分枝杆菌在发病过程中持续存在。我们将构造一组条件 以F420生物合成和代谢为靶点的击倒菌株，并进行体外研究，以确定M。 结核病在低氧条件下和低氧诱导休眠后的再生长过程中利用F420。我们会 然后在形成坏死性和缺氧性结核病变的小鼠模型上进行感染研究，以研究 F420如何促进肉芽肿内结核分枝杆菌的存活并了解F420与 坚持不懈。最后，我们将揭示F420发色团生物合成的结构见解，提供 F420生物合成中这一关键反应的机理和抑制研究的基础。

Project summary Mycobacterium tuberculosis, the causative agent of TB, remains an important cause of morbidity and mortality worldwide. Persistence in hypoxic conditions within granuloma is the hallmark of TB, leading to latent infection and limiting the application of current therapies. Understanding how M. tuberculosis supports its metabolism under hypoxic conditions, and adapts to these challenges, is key to eliminating latent TB. “Disarming” M. tuberculosis by removing its ability to endure the stress-inducing conditions in granuloma will provide a feasible strategy for clinical interventions against latent TB. We will investigate the role of the coenzyme F420 in the physiology and pathogenesis of M. tuberculosis. F420 is a deazaflavin that acts as a carrier in a wide range of hydride transfer reactions. Growing evidence points to the wide use of this cofactor by M. tuberculosis, with its low redox potential thought to give it key roles in hypoxic persistence. There appears to be F420-dependent mechanisms in mycobacteria that are used to protect against oxidative and nitrosative stress, but the contribution of F420 to M. tuberculosis metabolism and persistence remains unclear. The ultimate goal of the project is to investigate how F420 facilitates M. tuberculosis’ survival under hypoxic conditions within granuloma, elucidating its role in persistence. We have devised an integrated experimental approach using genetics, metabolomics, animal infection models, and protein biochemistry tools to determine how F420 helps M. tuberculosis persist during pathogenesis. We will construct a set of conditional knockdown strains targeting F420 biosynthesis and metabolism, and perform in vitro studies to determine how M. tuberculosis utilizes F420 under hypoxic conditions and during re-growth after hypoxia-induced dormancy. We will then perform infection studies in a mouse model that develops necrotic and hypoxic TB lesions to investigate how F420 facilitates M. tuberculosis survival inside granuloma and to understand the link between F420 and persistence. Finally, we will reveal structural insights into the biosynthesis of F420 chromophore, providing the foundations for mechanistic and inhibition studies of this essential reaction in F420 biosynthesis.