Growth phenotype of the M. tuberculosis PG100 triple mutant. The growth of the M. tuberculosis H37Rv wild-type plus pMD31 empty vector (■), PG100 mutant with pMD31 vector (▲), and complemented mutants (▼, ●) is shown. Complementation of PG100 with plasmid pPG72 (▼), which contained the Rv1403c-Rv1404-Rv1405c genes deleted from PG100, or with pPG57 (●), containing just the Rv1404 regulator, failed to restore the growth of the mutant to wild-type levels. Data shown are from one experiment, representative of three.