Positively regulates the expression of the exporter LysE. Induction requires the presence of a coinducer, which is either intracellular L-lysine, L-arginine or L-citrulline. L-histidine also acts as coinducer of lysE expression, but this amino acid is not exported by LysE (PubMed:11429454, PubMed:27350619). The lysEG system prevents bacteriostasis due to elevated L-lysine or L-arginine concentrations that arise during growth in the presence of peptides or in mutants possessing a deregulated biosynthesis pathway (PubMed:11429454). Deletion of lysEG decreases the extracellular accumulation of L-lysine, L-arginine and L-citrulline. Belongs to the LysR transcriptional regulatory family.