Figure legends
FIGURE 1 General regulatory mechanism of Rap-Phr pairs. (i) the Rap protein is produced and, (ii) carries its regulatory role intracellularly; meanwhile, (iii) pre-Phr proteins are produced, (iv) processed and exported out of the cell as Phr peptides; (v) upon reaching threshold concentrations, (vi) mature Phr peptides can be imported into the cell via the Opp permease and (vii) inhibit its cognate Rap protein. Rap proteins are visualized using the RapF crystal structure (PDB doi: 10.2210/pdb4I9E/pdb), while prePhr is depicted using the structure based on AlphaFold as displayed in SubtiWiki . The figure was prepared on BioRender.com.
FIGURE 2 Known cellular functions regulated by Rap phosphatases in B. subtilis . The centeral protein structure shows the conserved architecture of Rap phosphatases (RapF crystal structure, PDB doi: 10.2210/pdb4I9E/pdb). The biofilm colony images of wild type (WT) and ΔrapP mutant are taken from Nordgaard et al. (2021), scale bar represents 5 mm. The figure was prepared on BioRender.com.