TABLE 4.

Comparative expression of B. pseudomallei strain SZ5028 type III secretion genes in response to growth in M9 media containing 1.0% l-arabinose or d-glucose from analysis of 200-gene microarrays

GenePutative functionMean log2(IAra/IGlu) ± SD
bsaN Possible TTSS transcriptional regulator, similar to the AraC family regulatory protein−2.94 ± 1.30
bsaP TTSS secreted protein similar to mxiC gene in Shigella spp.−1.61 ± 0.91
bsaM Similar to prgH gene in Chromobacteria violaceum; TTSS inner membrane protein−1.02 ± 0.65
bprA Possible TTSS transcriptional regulator, similar to the H-NS DNA binding protein−1.29 ± 0.49
  • a Mean log2(IAra/IGlu) = average value of the log2-based ratio of intensities from two channels of the microarray: growth in arabinose versus growth in glucose. A negative number denotes down- regulation in arabinose. Only genes which displayed at least a twofold decrease [log2(IAra/IGlu) ≤ −1] in expression are listed. Results are the average of two independent RNA isolations with reverse labeling of each sample (dye swap), resulting in a total of four analyses.