FIG 10.

Model illustrating the impact of disruption of the Rgg2/3 QS system. Panel A illustrates what occurs when SHPs are added in a wild-type NZ131 background. Rgg3 binds SHPs and is released from target promoters, while Rgg2 binds SHPs and activates target promoters. This includes the SHP2/Rgg2 and SHP3/Rgg3 loci, as well as others such as the spy49_0450 operon and stcA. Normal Rgg2/3 QS occurs and a small number of target transcripts are affected. Panel B illustrates what occurs in the absence of Rgg3 with the addition of SHP peptide. Disruption of the system leads to an imbalance in QS activation, and this response is dependent on the presence of Rgg2. This results in a generalized stress response that alters the transcriptome and proteome of NZ131 cells.