FIG 2 .

Rv0078 represses the expression of Rv0077c. (A) The putative transcriptional start sites (+1) of Rv0077c and Rv0078 as determined by 5′ RACE and represented as bent arrows. The predicted start codons are in capital boldface letters. (B) EMSA analysis identifies a putative repressor binding site. Probe sequence +19/−14 refers to positions relative to Rv0077c position +1. In boldface is the presumed binding site. Mutated residues are in red. Not shown at the end of each probe is a sequence for annealing to a fluorescent tag (Table S1). Rv0078 was purified under native conditions from E. coli. (C) Deletion and disruption of Rv0078 result in the constitutive expression of Rv0077c. Total cell lysates were prepared and separated on a 10% SDS-PAGE gel. IB, immunoblot. The membrane was stripped and then incubated with antibodies to DlaT to confirm equal loading of samples. Molecular weight standards are indicated to the left of the blots and are in kilodaltons (kDa).