Characterization of the SouR regulon in Pseudomonas aeruginosa

The sarcosine oxidase locus is controlled by GbdR and SouR independently induced by glycine betaine and sarcosine, respectively. The goal of this study was to identify the members of the SouR regulon. Therefore, the comparison strains were a gbdR mutant and a gbdRsouR double mutant. The conditions for inclusion in the souR regulon were: (i) called present in the array, (ii) changed more than 2.5-fold in signal in a statistically significant manner, (iii) altered in the presence of sarcosine and dependent on souR. gbdR mutants and gbdR souR double mutants were pre-grown in MOPS minimal media and then split and resuspended in MOPS pyruvate or MOPS pyruvate + sarcosine.