RNA sequencing of Mtb H37Rv, MtbΔsufR and sufR complemented mycobacterium tuberculosis strains upon treatment with 0.5 mM DETA-NO.

Fe-S cluster proteins are involved in fundamental processes such as electron transfer, gene regulation, and DNA repair in diverse bacteria. Since Fe-S clusters are susceptible to damage by oxidative and nitrosative stress conditions, bacteria harbour systems such as ISC (iron-sulfur cluster assembly) and SUF (sulfur mobilization) to regulate Fe-S homeostasis. Fe-S cluster production is tightly regulated so as to promote Fe-S formation when the necessity for clusters is heightened (e.g., ROI/RNI/iron limitation) and to limit unnecessary production when the demand is low (e.g., hypoxia). Deregulation of Fe-S cluster biogenesis can lead to the accumulation of metabolic poisons such as polysulfides and reactive oxygen species. The human pathogen, Mycobacterium tuberculosis (Mtb) exploits several Fe-S containing proteins to maintain cellular homeostasis and survival in an antagonistic host environment. The Mtb genome encodes an atypical Suf system (Rv1460-Rv1466;sufRBDCSUT) as the only complete Fe-S cluster biogenesis machinery. Expression of sufR and the complete operon was shown to be upregulated upon exposure to nitrosative stresses. Thus, we did transcriptomic study of sufR deleted strain upon exposure to 0.5 mM DETA-NO to study comprehensively the suf regulon in response to ROI/RNI stress and what are the underlying regulatory mechanisms. The study involves profiling of mRNA signatures of these strains to show the important role of first gene of suf operon (sufR) to facilitate regeneration of Fe-S clusters during recovery from nitrosative stress. Wt Mtb H37Rv, MtbΔsufR and sufR complemented strains were grown till early log phase and exposed to 0.5 mM DETA-NO for 4 hours at 37 degree at 180rpm. Three independent experiments were done for each of the strain, respectively.