Transcriptomic analysis of Mtb Erdman, MtbΔvirS and MtbΔvirSComplement upon acidic stress of pH4.5

Since VirS was shown to be upregulated in acidic conditions and MtbΔvirS displayed defect in growth at pH4.5, we performed microarray at pH 6.6 and pH 4.5 to study the role of VirS in regulating gene expression at acidic pH. Early log phase grown cultures of Mtb Erdman, MtbΔvirS and MtbΔvirSComp were exposed to 7H9 media supplemented with ADC-Tween of pH of 6.6 and pH 4.5 for one hour at 37 degree at 200rpm. Mtb Erdman and MtbΔvirS, each had three replicates while MtbΔvirSComp has two replicates at both pH conditions i.e. pH 6.6 and pH 4.5. MtB Erdman and MtbΔvirSComp served as control for MtbΔvirS which was the test sample.