Figure 2.

Mapping of the identified Clusters residues on the regulatory domains of the QS LuxRs. Residues, belonging to Cluster 1 (in green), Cluster 2 (in cyan) and Cluster 3 (in orange) and labeled according to the TraR numbering scheme, have been mapped in (a), (c) and (e) on the X-ray crystal structure of TraR in complex with OC8-HSL (PDB_ID 1H0M [24]); in (b), (d) and (f) on the superimposed C_α traces of the representative structures of the regulatory domains of QS LuxR, showing the side chains orientations, with TraR (PDB_ID 1H0M [24]) in light pink, LasR (PDB_ID 3IX3) in light orange, QscR (PDB_ID 3SZT [28]) in light yellow; SdiA (PDB_ID 2AVX [30]) in light blue, CviR (PDB_ID 3QP1 [29]) in light green. The carbon, nitrogen and oxygen atoms of OC8-HSL, are colored in yellow, blue and red respectively. Figures produced by Pymol [33].