TABLE 7.

Expression of ilvBΔT-lacZ fusionsa

StrainRelevant genotypebFusion genotypeAddition to medium (no. of aa)β-Galactosidase activity
MU%c
BB2723Wild typeilvB6ΔTp+None681.0124
13467.085
16119.022
BB2603codYNone668.0121
16551.0100
BB2719Wild typeilvB6ΔTp1None393.070
13160.029
1618.03.2
BB2721codY16559.0100
BB2720Wild typeilvB6ΔTp2None721.0115
13507.081
16390.062
BB2722codY16626.0100
BB2753Wild typeilvB4ΔTp+13423.671
16104.118
BB2754codYilvB4ΔTp+16594.0100
BB2759Wild typeilvB+ΔTp+None1,130.0118
13777.081
16164.017
BB2760codY16955.0100
  • a Cells were grown and β-galactosidase activity (Miller units [MU]) was assayed as described for Table 2.

  • b All strains contained a lacA null mutation that eliminated endogenous β-galactosidase activity (9).

  • c The β-galactosidase activity of each fusion in the 16-aa-containing medium in a strain containing a codY null mutation was normalized to 100%.