FIG 2.

ResT half-life in B. burgdorferi. (A) To measure the half-life of ResT protein in the conditional expression strain (GCB2127), a time course analysis was performed using Western blotting following IPTG washout. B. burgdorferi was grown for 48 h in the presence of 1 mM IPTG until it reached late exponential phase. Following IPTG washout, the culture was diluted to 1.0 × 10⁶ spirochetes/ml (time zero) and incubation was continued for 48 additional hours, with aliquots removed at the indicated times. For Western blotting, 2.0 × 10⁷ spirochetes were loaded per well as described in Materials and Methods. ResT from the wild-type parent, B31-A, is also shown. Band intensities were quantified and analyzed using AlphaImager software (Alpha Innotech). (B) The half-life of ResT was calculated by plotting the percentage of ResT remaining versus time. Data in the graph represent two separate experiments. The calculated ResT half-life was 16 h.