Nitrogen metabolism in Mycobacterium tuberculosis: a systems-based approach

Several studies have already shown Mycobacterium tuberculosis (Mtb) obtains its carbon from host-derived nutrients and exploits specific metabolic pathways during infection.

In comparison to carbon, the processes Mtb uses to acquire and assimilate nitrogen (N) from the host is poorly studied despite N also being an essential component of biomolecules.

Our previous studies suggested the hypothesis that Mtb obtains N from a diverse range of intracellular nutrients including amino acids.

Here, we use a novel system’s based three-pronged approach to define pathways for uptake and assimilation of N. This consists of transposon mutagenesis, 15N isotopologueprofiling of intracellular Mtb, and performing flux analysis using 13C/15N isotopologue profiling in continuous culture.

Using this system’s strategy to study Mtb metabolism will help determine which N sources are required for ex vivo Mtb survival and the uptake and assimilation pathways involved to ultimately identify novel drug targets to treat TB.