Interplay between the Mtb electron transport chain and carbon metabolism

结核病是由结核分枝杆菌(Mtb)引起的，是主要的死亡原因。 在全世界范围内从一种可治愈的传染病中传播，并由于耐药性的传播而成为一个主要问题 结核分枝杆菌菌株。值得注意的是，结核分枝杆菌可以持续处于休眠、耐药状态，有时会重新激活以导致结核病。 在最初感染的几十年后。目前，人们对氧化磷酸化有浓厚的兴趣。 (OXPHOS)作为新的抗结核病药物和药物组合的代谢靶点。在这方面，有几个 靶向Mtb电子传递链(ETC)的抗分枝杆菌药物，包括贝达奎兰(第一个新的 ~40年的结核病药物)、Q203、氯法齐明和吩噻嗪。然而，如何抑制呼吸复合体 在ETC中，导致有效杀戮的因素尚未确定。我们认为，在我们的 理解OXPHOS如何与中枢碳分解代谢联系以响应变化 环境燃料来源对宿主的生存免疫反应和抗结核药物治疗。 我们的长期目标是确定使结核分枝杆菌在宿主体内存活的生物能量机制 处于休眠的、抗药性的状态。在这个提议中，我们的中心假设是Mtb之间的相互作用 等，中心碳分解代谢阻止了抗结核药物的有效杀戮。为了检验这一假设，我们有 建立了一系列特定的目标，以确定氧磷酸盐生成的ATP如何调节中央碳 分解代谢和琥珀酸排泄以维持代谢动态平衡，检查其机制 同时抑制OXPHOS和糖酵解可杀死结核分枝杆菌，并验证生物能量学假说 结核分枝杆菌临床菌株的动态平衡有助于药物耐受性。我们将利用一项新技术 被称为胞外通量(XF)的分析，我们已经适应于实时研究结核分枝杆菌生物能量学。这 技术的补充将是用液相色谱质谱进行13C稳定同位素分析 这一贡献是重大的，因为它有可能确定一种新的范式，这将导致 对Mtb ETC如何与中心碳分解代谢进行通信以及如何进行详细的机械理解 这一过程的中断可以被用来对结核分枝杆菌进行灭菌。这项提议在我们看来是创新的，因为 由代谢组学支持的新适应技术，将自己与传统方法区分开来 用于研究病原微生物的能量代谢。

Tuberculosis, caused by the etiological agent Mycobacterium tuberculosis (Mtb), is the leading cause of death worldwide from a curable infectious agent and is becoming a major concern due to the spread of drug resistant Mtb strains. Notably, Mtb can persist in a dormant, drug resistant state, sometimes reactivating to cause TB decades after the primary infection. Currently, there is strong interest in exploiting oxidative phosphorylation (OXPHOS) as a metabolic target for new anti-TB drugs and drug combinations. In this regard, there are several antimycobacterial drugs that target the Mtb electron transport chain (ETC), including bedaquiline (the first new TB drug in ~40 years), Q203, clofazimine, and phenothiazines. However, how inhibition of respiratory complexes in the ETC leads to effective killing has yet to be established. We believe there is a critical gap in our understanding of how OXPHOS communicates with central carbon catabolism in response to changing environmental fuel sources to survive the host immune response and anti-TB drug therapy. Our long-term goal is to define the bioenergetic mechanisms that enable Mtb to survive within the host in a dormant, drug resistant state. In this proposal, our central hypothesis is that the interplay between the Mtb ETC and central carbon catabolism prevents effective killing by anti-TB drugs. To test this hypothesis, we have established a series of specific aims to determine how OXPHOS-generated ATP modulates central carbon catabolism and succinate excretion to maintain metabolic homeostasis, examine the mechanisms whereby simultaneous inhibition of OXPHOS and glycolysis kills Mtb, and test the hypothesis that bioenergetic homeostasis in clinical strains of Mtb contributes to drug tolerance. We will make use of a novel technology termed extracellular flux (XF) analysis that we have adapted for studying Mtb bioenergetics in real time. This technology will be complemented by 13C stable isotope analyses using liquid chromatography mass spectrometry This contribution is significant, because it has the potential to identify a new paradigm that will lead to a detailed mechanistic understanding of how the Mtb ETC communicates with central carbon catabolism, and how disruption of this process could be exploited to sterilize Mtb. This proposal is innovative in our opinion, because the newly adapted technology that is supported by metabolomics, distinguish itself from conventional approaches for studying energy metabolism in pathogenic microbes.