Fig. 5.

Model for the role of teichoic acids synthesis in PBP4 recruitment to the septum. The early cell-wall synthetic machinery assembles at the division site, leading to the synthesis of new PGN, with low levels of cross-linking (Left). TagO (together with other WTA synthetic enzymes) is recruited to the septum by an unknown mechanism, leading to the synthesis of intermediate molecules in TA biosynthesis (Center). These intermediates (or another cellular component dependent on TA biosynthesis) function as a temporal and spatial cue for PBP4 recruitment to the division septum, allowing the synthesis of highly cross-linked PGN to occur in a regulated manner (Right).