TABLE 3

Urocanate-induced hut gene expression in strains that carry polar mutations of the hut loci

β-Galactosidase (aM 4MU min−1 cell−1)a
Fusion strainGenetic backgroundM9M9 + urocanateb
PBR812hutC-‘lacZ, wild type0.88 ± 0.132.90 ± 0.43 (S)
PBR816hutC-‘lacZ, hutC∷Ω5.37 ± 0.534.80 ± 0.42 (NS)
PBR813hutU-‘lacZ, wild type1.69 ± 0.0427.65 ± 1.33 (S)
PBR817hutU-‘lacZ, hutC∷Ω81.38 ± 3.1543.66 ± 3.83 (S)
PBR832hutU-‘lacZ, hutU∷Ω8.12 ± 0.4855.59 ± 2.85 (S)
PBR814hutG-‘lacZ, wild type0.96 ± 0.117.42 ± 1.83 (S)
PBR818hutG-‘lacZ, hutC∷Ω34.48 ± 3.1333.22 ± 9.49 (NS)
PBR819hutG-‘lacZ, hutU∷Ω1.45 ± 0.071.30 ± 0.35 (NS)
  • a β-Galactosidase activities were measured for cells growing in minimal-M9 medium (M9) and M9 supplemented with urocanate (M9 + urocanate).

  • b Data are means and standard errors of three independent cultures from eight independent experiments. Each experiment was designed to test the hypothesis that the fusion is urocanate inducible. Results of paired t-tests are provided: S and NS indicate significant and nonsignificant induction (P < 0.05), respectively.