Proteomics of Culture Filtrate of Prevalent Mycobacterium tuberculosis Strains: 2D-PAGE Map and MALDI-TOF/MS Analysis

Abstract

Although diverse efforts have been done to identify biomarkers for control of tuberculosis using laboratory strain <i>Mycobacterium tuberculosis</i> H37Rv, the disease still poses a threat to mankind. There are many emerging <i>M. tuberculosis</i> strains, and proteomic profiling of these strains might be important to find out potential targets for diagnosis and/or prevention of tuberculosis. We evaluated the comparative proteomic profiling of culture filtrate (CF) proteins from prevalent <i>M. tuberculosis</i> strains (Central Asian or Delhi type; CAS1_Del, East African-Indian; EAI-3 and Beijing family) by 2D polyacrylamide gel electrophoresis and matrix-assisted laser desorption ionization-time-of-flight mass spectrometry. As a result, we could identify 12 CF proteins (Rv0066c, Rv1310, Rv3375, Rv1415, Rv0567, Rv1886c, Rv3803c, Rv3804c, Rv2031c, Rv1038c, Rv2809, and Rv1911c), which were consistently increased in all prevalent <i>M. tuberculosis</i> strains, and interestingly, two CF proteins (Rv2809, Rv1911c) were identified with unknown functions. Consistent increased intensity of these proteins suggests their critical role for survival of prevalent <i>M. tuberculosis</i> isolates, and some of these proteins may also have potential as diagnostic and vaccine candidates for tuberculosis, which needs to be further explored by immunological analysis.