M.tb-Rv2462c of Mycobacterium tuberculosis Shows Chaperone-like Activity and Plays a Role in Stress Adaptation and Immunomodulation.

Mycobacterium tuberculosis ( M.tb )-encoded factors protect it against host-generated stresses and support its survival in the hostile host environment. M.tb possesses two peptidyl-prolyl cis-trans isomerases and a probable trigger factor encoded by Rv2462c which has an FKBP-like PPIase domain. PPIases are known to assist the folding of peptidyl-prolyl bonds and are involved in various cellular processes important for bacterial survival in host-generated stresses. In this study, we aim to functionally characterize Rv2462c of M.tb. Our data suggest that the trigger factor of M.tb exhibits chaperone activity both in vitro and in vivo. Heterologous expression of M.tb - Rv2462c locus into Mycobacterium smegmatis enhanced its survival within macrophages, adaptation to oxidative stress and biofilm formation. M.tb -trigger factor has strong immunomodulatory potential and modifies the cytokine profile of the host towards the proinflammatory axis.