May modulate activity of the MtrAB system in controlling homeostasis of the cell wall and cell division. Interacts with MtrB, probably extracytoplasmically via its sensor domain. Increased antibiotic susceptibility, altered colony morphology and increased aggregation, increased uptake of the Congo Red stain and increased sensitivity to SDS. Decreased gliding motility and biofilm formation. Cells are very long, sometimes branched and often polyploid. Decreased phosphorylation of MtrA, increased expression of dnaA in early growth stages. Belongs to the LpqB lipoprotein family.