A. The ESAT-6 sequences from M. tuberculosis, M. bovis, M. marinum, M. smegmatis, M. leprea, and M. avium were aligned with ClustalW2. The residues are colored according to chemical natures: Red (hydrophobic), Green (polar), Blue (acidic), Magenta (basic). The conserved WXG and HxxxD/ExxHxxxH motifs are boxed. B. The phylogenic tree was calculated in ClustalW2.