MAB_3551c encodes the primary triacylglycerol synthase involved in lipid accumulation in Mycobacterium abscessus

摘要: Slow growing pathogenic mycobacteria utilize host-derived lipids and accumulate large amounts of triacylglycerol (TAG) in the form intracytoplasmic lipid inclusions (ILI), serving as a source carbon energy during prolonged infection. Mycobacterium abscessus is an emerging rapidly species capable to induce severe chronic pulmonary infections. However, whether M. abscessus, like tuberculosis, possesses machinery acquire store host lipids, remains unaddressed. Herein, we aimed at deciphering contribution seven putative TAG synthases (Tgs) synthesis/accumulation thanks combination genetic biochemical techniques well-defined foamy macrophage (FM) model along with electron microscopy. Targeted gene deletion functional complementation studies identified MAB_3551c product, Tgs1, major Tgs involved production. Tgs1 exhibits preference for long acyl-CoA substrates site-directed mutagenesis demonstrated that His144 Gln145 are essential enzymatic activity. Importantly, lipid-rich intracellular context FM, formed ILI Tgs1-dependent manner. This supports ability assimilate crucial role intramycobacterial production, which may represent important mechanisms long-term storage rich supply. article protected by copyright. All rights reserved.