IS 6110 insertion in the phoP promoter in BCG-Russia, -Moreau, and -Japan. (A) Schematic representation of the phoP-phoR locus with IS6110 inserted in an inverse orientation 18 bp upstream from phoP start codon. (B) Nucleotide sequence surrounding IS6110. The IS6110 sequence is boxed. The GAA direct repeats flanking the IS6110 insertion site is underlined and in boldface. The ATG start codons of phoP and phoR are indicated by arrows and in boldface.