Role of MSMEG_2295 in controlling Mycobacterium smegmatis gene expression

MSMEG_2295 is a TetR family protein encoded by the first gene of a Mycobacterium smegmatis (Msm) operon that expresses the gene for DinB2 (MSMEG_2294), a translesion DNA repair enzyme. We have carried out investigations to understand its function by performing DNA binding studies and gene knockout experiments. We found that the protein binds to a conserved inverted repeat sequence located upstream of the dinB2 operon and several other genes. Using a knockout of MSMEG_2295, we show that MSMEG_2295 controls the expression of at least five genes, the products of which could potentially influence carbohydrate and fatty acid metabolism as well as antibiotic and oxidative stress resistance.