Comparative proteomic analysis of Mycobacterium tuberculosis strain H[37]Rv versus H[37]Ra

ABSTRACT

Mycobacterium tuberculosis [MTB] H[37]Ra is an attenuated tubercle bacillus closely related to the virulent type strain MTB H[37]Rv. In spite of extensive study, variation in virulence between the MTB H[37]Rv and MTB H[37]Ra strains is still to be understood. The difference in protein expression or structure due to mutation may probably be an important factor for the virulence property of MTB H[37]Rv strain. In this study, a whole proteome comparison between these two strains was carried out using bioinformatics approaches to elucidate differences in their protein sequences. On comparison of whole proteome using NCBI standalone BLAST program between these two strains, 3759 identical proteins in both the strains out of 4003 proteins were revealed in MTB H[37]Rv and 4034 proteins were revealed in MTB H[37]Ra; 244 proteins of MTB H[37]Rv and 260 proteins of MTB H[37]Ra were found to be non-identical. A total of 172 proteins were identified with mutations [Insertions/deletions/substitutions] in MTB H[37]Ra while 53 proteins of MTB H[37]Rv and 85 proteins of MTB H[37]Ra were found to be distinct. Among 244 non-identical proteins, 19 proteins were reported to have an important biological function; In this study, mutation was shown in these proteins of MTB H[37]Ra. This study reports the protein differences with mutations between MTB H[37]Rv and H[37]Ra, which may help in better understanding the pathogenesis and virulence properties of MTB H[37]Rv