FIG 8.
Effect of single alanine substitutions in the last 5 residues of the RD-I subdomain at the C terminus on LeuO regulatory functions. (A and B) Transcriptional profiles of ompS1 and tpx genes in S. Typhi with the LeuO wt or with five mutants with different alanine-substituted residues: LeuOS310A, LeuOV311A, LeuOC312A, LeuOK313A, and LeuOR314A. (C) Expression of the LeuO wt and mutated proteins was evaluated by Western blotting after SDS-PAGE using an anti-LeuO polyclonal antibody and an anti-DnaK monoclonal antibody as a control. The cultures were grown in MA medium to an OD595 of 1.0, and expression of the proteins was induced with 100 μM IPTG.