Interplay between the Mtb electron transport chain and carbon metabolism

由病原体结核分枝杆菌（Mtb）引起的结核病是导致死亡的主要原因 由于耐药性细菌的传播， 结核病菌株。值得注意的是，结核分枝杆菌可以持续处于休眠、耐药状态，有时会重新激活导致结核病 在初次感染后几十年。目前，人们对利用氧化磷酸化有浓厚的兴趣 （OXPHOS）作为新的抗TB药物和药物组合的代谢靶标。在这方面， 靶向Mtb电子传递链（ETC）的抗分枝杆菌药物，包括贝达喹啉（第一个新的 约40年的结核病药物）、Q203、氯法齐明和吩噻嗪。然而，如何抑制呼吸复合物 在ETC导致有效的杀戮尚未建立。我们认为，在我们的 了解OXPHOS如何与中央碳催化剂通信，以应对变化 环境燃料来源，以生存的主机免疫反应和抗结核病药物治疗。 我们的长期目标是确定使结核分枝杆菌在宿主体内生存的生物能量机制 处于一种休眠的抗药状态在这个提议中，我们的中心假设是结核分枝杆菌之间的相互作用 ETC和中央碳催化剂阻止抗结核药物的有效杀死。为了验证这个假设，我们有 建立了一系列具体的目标，以确定OXPHOS产生的ATP如何调节中心碳 代谢平衡，检查其机制， 同时抑制OXPHOS和糖酵解杀死结核分枝杆菌，并测试生物能 结核分枝杆菌临床菌株的体内平衡有助于药物耐受性。我们将利用一种新技术 称为细胞外通量（XF）分析，我们已将其用于真实的时间研究Mtb生物能量学。这 这项技术将得到利用液相色谱质谱法进行13 C稳定同位素分析的补充 这一贡献意义重大，因为它有可能确定一个新的范式， 详细了解Mtb ETC如何与中央碳催化剂通信，以及如何 可以利用该过程的中断来杀灭Mtb。我们认为这项建议是创新的，因为 由代谢组学支持的新适应技术将其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.