2D DIGE proteomic analysis of multidrug resistant and susceptible clinical Mycobacterium tuberculosis isolates

Tuberculosis (TB) is the leading cause of infectious disease related mortality worldwide. Infection of Mycobacterium tuberculosis (Mtb) leads to nearly 3 million deaths every year due to tuberculosis. Rifampicin and Isoniazid (RH) are the key drugs to being used for the treatment of tuberculosis. Reports in recent years indicate that the increasing emergence of resistance to these drugs. The resistance to these drugs severely affects options for effective treatment. The current vaccine for tuberculosis has variable protective efficacy and there is no commercially available serodiagnostic test for this disease with acceptable sensitivity and specificity for routine laboratory use, especially in case of multidrug resistance. In order to develop a new diagnostic tool for detection of Mtb, multidrug resistant Mtb as well and improve the tuberculosis vaccine, it is necessary to indentify novel antigenic candidates, especially in identification of multidrug resistant associated protein antigens. Here, we present a 2-D gel-based proteomic survey of the changes in RH resistant Mtb. The proteins extracted from RH resistant and susceptible Mtb clinical isolates were analyzed by two-dimensional differential in gel electrophoresis (2D-DIGE). Protein intensities of 41 spots were found to be regulated in RH resistant isolates. A total of 28 proteins were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Twelve proteins of interest are NADH-dependent enoyl-[acyl-carrier-protein] reductase, 60 kDa chaperonin 2, Chaperone protein DnaK, 3-oxoacyl-(Acyl-carrier-protein0 reductase, Probable acetyl-CoA acyltransferase FadA2, two Acetyl/propionyl-CoA carboxylase, alpha subunit, Universal stress protein Rv1636/MT1672, Dihydrolipoyllysine-residue acetyltransferase component of pyruvate dehydrogenase complex, Glutamine synthetase 1 and two uncharacterized proteins (Rv2557 and Rv1505c)