Systems-based screen of compounds that target nitrogen metabolism of Mycobacterium tuberculosis.

基于系统的筛选针对结核分枝杆菌氮代谢的化合物。

• 批准号: BB/V010611/1
• 负责人: Johnjoe McFadden
• 金额: $ 95.88万
• 依托单位: University of Surrey
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FV010611%2F1
• 关键词: Systems; based; screen; compounds; target

M. tuberculosis (Mtb), the etiological agent of TB, is presently the most devastating infectious agent of mortality worldwide, responsible for about 8 million cases of TB each year resulting in more than one million deaths. Co-infection with the human immunodeficiency virus (HIV), along with the emergence of multi- and extensively- drug resistant (MDR and XDR) strains of TB, has reaffirmed Mtb as a primary public health threat throughout the world. The limited number of drugs available that have activity against Mtb, and the prolonged multi-drug regimen needed to eradicate the infection, are the fundamental problems of TB treatment. New drugs active against Mtb are urgently needed. Intracellular metabolism of Mtb is an attractive target for development of novel anti-tuberculosis drugs; however most studies have focussed on carbon metabolism. Nitrogen is also an essential nutrient of Mtb but few studies have attempted to elucidate fundamental questions such as the nature of the nitrogen source of the pathogen when it grows inside the host. Our previous studies have identified the principle amino acids as sources of nitrogen for Mtb when growing inside host cells. In this study we aim to take this study forward to test the hypothesis that nitrogen metabolism represents an unexplored and potentially fruitful drug target for TB drug development. We will use serine metabolism as a test case of this hypothesis. In our previous study we demonstrated that the enzyme SerC that performs the last step in the biosynthesis of serine is essential for intracellular replication of Mtb. This suggest that it is also essential for growth of the pathogen inside the host and thereby a good target for the development of novel drugs. To confirm this hypothesis, we will first measure the virulence of the SerC mutant of Mtb in a mouse model of infection. The next step will be to screen a 'library' of chemical compounds library to identify any that target SerC. Conventional drug screens identify compounds that are active against particularly enzymes, such as SerC. However, the identified compounds often fail to work in the natural host because of poor penetration or inactivation of the drug in host cells. To overcome this problem, we propose to screen compounds against whole live cells of Mtb. This is more difficult as Mtb makes hundreds of different enzymes, each of which might be inhibited by the test compounds. To identify compounds that specifically target SerC, we will search for those that are active against wild-type Mtb but not a SerC mutant strain supplemented with serine so that it no longer needs SerC to grow. We will then extend the study to other key genes involved in nitrogen metabolism and uptake of amino acids from host cells. Finally, we will develop a computer model of nitrogen and carbon metabolism in Mtb that can be used to design combinations of drugs that target nitrogen metabolism that will work effectively together and test predictions of the model experimentally.

M.结核病（Mtb），即TB的病原体，目前是全世界最具破坏性的致死性传染源，每年造成约800万例TB病例，导致超过100万人死亡。与人类免疫缺陷病毒（HIV）的共感染，沿着结核病的多重和广泛耐药（MDR和XDR）菌株的出现，再次证实了结核分枝杆菌是全世界的主要公共卫生威胁。对结核分枝杆菌具有活性的药物数量有限，以及根除感染所需的长期多药方案是结核病治疗的根本问题。迫切需要抗结核病的新药。结核分枝杆菌的细胞内代谢是开发新型抗结核药物的一个有吸引力的靶点;然而，大多数研究都集中在碳代谢上。氮也是结核分枝杆菌的必需营养素，但很少有研究试图阐明基本问题，如病原体在宿主体内生长时的氮源性质。我们以前的研究已经确定了Mtb在宿主细胞内生长时作为氮源的主要氨基酸。在这项研究中，我们的目标是将这项研究向前推进，以测试氮代谢代表结核病药物开发的一个未探索的和潜在的富有成效的药物靶点的假设。我们将使用丝氨酸代谢作为这一假设的测试案例。在我们以前的研究中，我们证明了在丝氨酸生物合成中进行最后一步的酶SerC对于Mtb的细胞内复制是必不可少的。这表明它对于病原体在宿主内的生长也是必不可少的，从而是开发新药的良好靶标。为了证实这一假设，我们将首先测量Mtb的SerC突变体在小鼠感染模型中的毒力。下一步将是筛选一个化学化合物库，以识别任何靶向SerC的化合物。传统的药物筛选鉴定对特定酶（如SerC）有活性的化合物。然而，由于药物在宿主细胞中的渗透性差或失活，所鉴定的化合物通常不能在天然宿主中起作用。为了克服这个问题，我们提出了针对结核分枝杆菌的整个活细胞筛选化合物。这是更困难的，因为结核分枝杆菌使数百种不同的酶，其中每一种都可能被测试化合物抑制。为了鉴定特异性靶向SerC的化合物，我们将寻找那些对野生型Mtb有活性但对补充丝氨酸的SerC突变株没有活性的化合物，这样它就不再需要SerC来生长。然后，我们将研究扩展到其他参与氮代谢和从宿主细胞中摄取氨基酸的关键基因。最后，我们将开发结核分枝杆菌氮和碳代谢的计算机模型，该模型可用于设计靶向氮代谢的药物组合，这些药物组合将有效地协同工作，并通过实验测试模型的预测。

项目成果

Dissecting Host-Pathogen Interactions in TB Using Systems-Based Omic Approaches.

• DOI: 10.3389/fimmu.2021.762315
• 发表时间: 2021
• 期刊: Frontiers in immunology
• 影响因子: 7.3
• 作者: Borah K;Xu Y;McFadden J
• 通讯作者: McFadden J

One-shot 13C15N-metabolic flux analysis for simultaneous quantification of carbon and nitrogen flux

一次性 13C15N 代谢通量分析可同时定量碳和氮通量

• DOI: 10.3929/ethz-b-000605263
• 发表时间: 2023
• 作者: Slater, Khushboo Borah

Razor sharp: The role of Occam's razor in science

剃刀锋利：奥卡姆剃刀在科学中的作用

• DOI: 10.1111/nyas.15086
• 发表时间: 2023
• 期刊: Annals of the New York Academy of Sciences
• 影响因子: 5.2
• 作者: McFadden J

Metabolic flux reprogramming in Mycobacterium tuberculosis-infected human macrophages.

• DOI: 10.3389/fmicb.2023.1289987
• 发表时间: 2023
• 期刊: Frontiers in microbiology
• 影响因子: 5.2