FIG. 5.

Expression of multiple genes is influenced by both pH 7.5 and 0.15 M NaCl. Total levels of RNA prepared from cultures grown to early stationary phase in C medium buffered with 0.1 M HEPES (pH 7.5) or in C medium supplemented with an additional 0.15 M NaCl were analyzed in competitive hybridization with cDNA from control cultures (unmodified C medium) by use of S. pyogenes DNA microarrays as described in Materials and Methods. Each gene included in the analysis is represented by a diamond; each value represents the average severalfold change in transcript abundance relative to results obtained with unmodified medium. Dashed lines denote twofold changes, and black diamonds represent genes that had statistically significant differential expression results in both experimental conditions from those seen under control conditions as described in Materials and Methods. See Table 1 and Table 2 for gene names and values.