Mycobacterium tuberculosis H37Rv Genome sequencing. Mycobacterium tuberculosis H37Rv

The intracellular nature of the mycobacteria has hindered the isolation of bacterial mRNA and limited RNAseq studies to bacterial cultures and in in-vitro cell infections. We describe a differential cellular lysis strategy, followed by a biotinylated probe-based ribosomal depletion, to simultaneously obtain the gene expression of Mtb inside BALB/c mouse lungs 21 days after the infection, which represents the peak of immune protection in this experimental model. We found 702 expressed mycobacterial genes, with a highlighted presence of PPE-PGRS, fatty acid synthesis, and cross-talk interaction genes such as LpqH and PstS1. Interestingly, 38.41% of the Mtb sequences corresponded to five intergenic regions, including small regulatory RNA MTS2823. Regarding the host, the most expressed genes were related to cell migration and activation, phagolysosome activity, antigen presentation, and antibody production.