Sharma Taruna, Tyagi Shaifali, Pal Rahul, Kundu Jayendrajyoti, Gupta Sonu Kumar, Barik Vishawjeet, Nain Vaibhav Kumar, Pandey Manitosh, Dwivedi Prabhanjan, Panda Bhishma Narayan, Kumar Yashwant, Nanda Ranjan Kumar, Chatterjee Samrat, Pandey Amit Kumar
Mycobacterial Pathogenesis Laboratory, Centre for Tuberculosis Research, Translational Health Science and Technology Institute, Faridabad, Haryana, India.
Jawaharlal Nehru University, New Delhi, Delhi, India.
mSystems. 2025 Jul 22;10(7):e0042025. doi: 10.1128/msystems.00420-25. Epub 2025 Jun 30.
The long-term survival of (Mtb) requires efficient use of host resources and uninterrupted access to host-derived nutrients. This is done by utilization of a highly flexible and integrated network of metabolic pathways. Phosphoglucomutase A () is essential for glycogen biosynthesis, which acts as a nutrient reservoir and is known to modulate carbon flux in various pathogens. We, for the first time, investigated the role of in Mtb by creating a strain lacking this gene. The absence of hinders the survival of pathogens under nutrient-limiting and reactivation conditions. Our study shows that the lack of cell membrane-associated glycolipids in Δ compromises cell wall integrity and increases susceptibility to stress. Interestingly, Δ exhibits an enhanced growth phenotype on cholesterol compared to the wild type due to low cyclic adenosine monophosphate (cAMP) levels. Differential gene expression and C carbon dilution analyses indicate that stored carbon as glycogen is crucial for Mtb survival under nutrient-limiting conditions. We demonstrate that is vital for Mtb growth within the host. This study highlights the critical role of in metabolic adaptation during nutrient starvation and reactivation and its implication on antibiotic and disease persistence. These insights are crucial for developing novel, shorter, and more effective anti-tuberculosis strategies.IMPORTANCEThis study for the first time investigated the role of metabolic enzyme phosphoglucomutase A () in (Mtb), revealing its crucial functions as a toggle switch between biosynthesis and growth. This work highlights the importance of in maintaining the metabolic flexibility of Mtb during the nutritional switch. The presence of is critical for the production of membrane-associated glycolipid, which helps maintain the cell wall integrity under various growth and stress conditions. This adaptability is pivotal for generating starvation-induced antibiotic tolerance in Mtb. In addition to the clinical context, these findings provide a mechanistic foundation for understanding adaptive strategies by Mtb to harsh environments and the development of drug-tolerant bacilli.
结核分枝杆菌(Mtb)的长期存活需要有效利用宿主资源并持续获取宿主衍生的营养物质。这是通过利用一个高度灵活且整合的代谢途径网络来实现的。磷酸葡萄糖变位酶A(PgmA)对于糖原生物合成至关重要,糖原作为一种营养储备,已知可调节多种病原体中的碳通量。我们首次通过构建缺失该基因的菌株来研究PgmA在Mtb中的作用。PgmA的缺失阻碍了病原体在营养限制和再激活条件下的存活。我们的研究表明,ΔPgmA菌株中缺乏与细胞膜相关的糖脂会损害细胞壁完整性并增加对应激的敏感性。有趣的是,由于环磷酸腺苷(cAMP)水平较低,与野生型相比,ΔPgmA菌株在胆固醇上表现出增强的生长表型。差异基因表达和¹³C碳稀释分析表明,作为糖原储存的碳对于Mtb在营养限制条件下的存活至关重要。我们证明PgmA对于Mtb在宿主体内的生长至关重要。这项研究突出了PgmA在营养饥饿和再激活期间的代谢适应中的关键作用及其对抗生素和疾病持续性的影响。这些见解对于开发新型、更短且更有效的抗结核策略至关重要。
重要性
本研究首次调查了代谢酶磷酸葡萄糖变位酶A(PgmA)在结核分枝杆菌(Mtb)中的作用,揭示了其作为生物合成与生长之间的切换开关的关键功能。这项工作突出了PgmA在营养转换期间维持Mtb代谢灵活性的重要性。PgmA的存在对于膜相关糖脂的产生至关重要,这有助于在各种生长和应激条件下维持细胞壁完整性。这种适应性对于在Mtb中产生饥饿诱导的抗生素耐受性至关重要。除了临床背景外,这些发现为理解Mtb对恶劣环境的适应性策略以及耐药物杆菌的发展提供了机制基础。