Target and Non-target Based Resistance to Bedaquiline in South Africa

结核病是世界范围内可治愈的传染性病原体导致死亡的主要原因， 由于耐药结核分枝杆菌（Mtb）菌株的传播，2015年，南非 国家结核病规划署引入贝达喹啉（BDQ），以加强现有的治疗方案 利福平耐药结核病这一倡议对成千上万的南方国家有着直接和深远的影响。 非洲人患结核病。令人担忧的是，与BDQ抗性相关的突变（rv 0678和atpE） 在从从未用BDQ或氯法齐明（CFZ）治疗的患者中分离的Mtb克隆中鉴定出。 有趣的是，BDQ和CFZ都靶向Mtb电子传递链。这些发现，加上事实， Mtb可以在休眠，耐药状态下持续存在，有时会在数十年后重新激活导致结核病， 原发性感染，表明迫切需要更好地了解BDQ/CFZ耐药的临床机制 结核分枝杆菌菌株 我们的长期目标是了解结核分枝杆菌耐药性的机制，以及这些知识如何能够 用于预防和治疗目的。在这个提议中，我们的中心假设是 rv 0678，atpE和Mtb基因组其他地方的突变使中枢代谢失调， BDQ和CFZ电阻。为了验证这一假设，我们建立了一个全球合作的努力， 南非Sefako Makgatho健康科学大学（SMU）的基础和临床研究人员以及 亚拉巴马大学伯明翰分校。作为合作的一部分，我们建立了一系列 具体目的是确定rv 0678和atpE突变在分离自 南非的病人。我们还将利用一种新的技术，称为细胞外通量（XF 96）分析 用于真实的研究结核病生物能量学。这项技术将得到13 C的补充 使用液相色谱质谱法进行稳定同位素分析。最后，我们将继续努力， 令人兴奋的初步发现，并确定是否BDQ耐药相关的变异有助于杆菌的 生物能量灵活性 这一贡献意义重大，因为它有可能确定一个新的范式， 对BDQ/CFZ耐药性出现的机制理解，以及如何破坏这一过程， 用于消灭结核分枝杆菌。我们认为这项建议是创新的，因为新采用的技术 由全基因组测序、实时生物能量学和代谢组学支持的 从传统的方法来研究病原微生物的耐药性。

Tuberculosis 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 Mycobacterium tuberculosis (Mtb) strains. In 2015, the South African National Tuberculosis Programme introduced Bedaquiline (BDQ) to strengthen existing regimens for the therapy of rifampicin-resistant TB. This initiative has immediate and far-reaching implications for thousands of South Africans suffering from TB. Concerningly, mutations associated with BDQ resistance (rv0678 and atpE) have been identified in Mtb clones isolated from patients who have never been treated with BDQ or clofazimine (CFZ). Intriguingly, both BDQ and CFZ target the Mtb electron transport chain. These findings, together with the fact that Mtb can persist in a dormant, drug-tolerant state, sometimes reactivating to cause TB decades after the primary infection, indicate an urgent need to better understand the mechanisms of BDQ/CFZ resistance in clinical strains of Mtb. Our long-term goal is to understand the mechanisms of Mtb drug resistance and how this knowledge can be used for prophylactic and therapeutic purposes in South Africa. In this proposal, our central hypothesis is that mutations in rv0678, atpE and elsewhere in the Mtb genome dysregulate central metabolism that contributes to BDQ and CFZ resistance. To test this hypothesis, we have established a global collaborative effort between basic and clinical investigators at Sefako Makgatho Health Sciences University (SMU) in South Africa and the University of Alabama at Birmingham (UAB). As part of this collaboration, we have established a series of specific aims to determine the prevalence of rv0678 and atpE mutations in specific Mtb lineages isolated from patients in South Africa. We will also make use of a novel technology termed extracellular flux (XF96) 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. Lastly, we will further pursue our exciting preliminary findings and determine whether BDQ resistance associated variants contribute to the bacilli's bioenergetic flexibility. This contribution is significant, because it has the potential to identify a new paradigm that will lead to a mechanistic understanding of the emergence of BDQ/CFZ resistance, 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 whole genome sequencing, real-time bioenergetics and metabolomics, distinguishes itself from conventional approaches for studying drug resistance in pathogenic microbes.