Fig 6.

Manganese downregulates BosR at the posttranscriptional level. (A) Addition of MnCl₂ downregulates BosR at the posttranscriptional level. Strain B31-A3 was grown at 37°C in Chelex-treated BSK-II medium (pH 7.0) with or without addition of 10 μM MnCl₂. Spirochetes were harvested at the late log phase and subjected to qRT-PCR (left panel) and immunoblotting analyses (right panel). qRT-PCR data are from 3 independent samples with significance determined by Student's t test. A representative result from immunoblotting of samples is shown. (B and C) The bmtA mutant in a 297 background (B) or a B31 background (C) enhances BosR protein at the posttranscriptional level. The parental strains and the isogenic bmtA mutant were grown in BSK-II medium (pH 7.5) at 37°C and harvested at the late logarithmic phase. Spirochetes were then subjected to qRT-PCR (left panel) and representative immunoblotting analyses (right panel) as described for panel A.