Tn-seq to investigate the genes essential for MABS and MABR

Mycobacterium abscessus (MAB) is a globally emerging pathogen responsible for a wide range of infections, characterized by colonies displaying either a smooth (MABS) or rough (MABR) morphotype. During infection, MABS may transition to the MABR morphotype, which has been associated with increased pathogenicity and worse clinical outcomes. To better understand the physiological differences between these two morphotypes, we conducted transposon insertion sequencing (Tn-seq) to quantitatively assess gene essentiality. Tn-seq was performed on frozen library stocks, libraries grown to mid-log phase, and samples collected from a murine abscess model. This approach allowed us to identify morphotype-specific essential genes and evaluate the impact of various conditions on gene essentiality.