FIG 6.

Evaluation of growth, RPMI 1640 survival, and relative RNA expression phenotypes for B. burgdorferi 297 wild-type (WT) and the 297 ΔdksA mutant strains. (A) Spirochetes were enumerated by microscopy. Values represent average from two replicates, and bars indicate standard deviation. (B) Mid-logarithmic-phase cultures of 297 wild-type, ΔdksA mutant, and ΔdksA pDksA mutant strains grown in BSK II medium were pelleted and resuspended in RPMI 1640 medium for 0 or 48 h before plating on semisolid BSK II medium, and CFU were enumerated following growth. The P values represent ANOVA with Dunnett’s multiple-comparison results from three replicate experiments. (C) Comparison of dksA-dependent gene expression in B31-A3 by microarray and 297 by RT-qPCR. Differential expression data of housekeeping genes (rpoD and flaB) and surface-expressed lipoprotein genes (dbpA, bba66, and ospC) are represented side by side. Relative expression values from RT-qPCR in the 297 strains represent 3 biological replicates and were normalized to 16S rRNA. Bars represent standard deviation.