Fig 6.

Putative model of the GraRS-VraFG network. In this model, GraS senses CAPs selectively, resulting in its autophosphorylation. GraS then phosphorylates GraR, driving mprF and dlt expression in a vraFG-dependent manner. VraFG can also affect expression of mprF and dlt via a positive feedback mechanism. MprF and DltABCD encode proteins which add positively charged lysine and d-alanine to membrane phospholipids and cell wall teichoic acids, respectively, to increase the surface positive charge (44, 46, 53, 54). VraFG may function to efflux CAPs (26). PLs, phospholipids; TAs, teichoic acids. A blue arrow indicates transcriptional upregulation.