Figure 4. Exposed DNA binding surfaces of RpoE10 adopt a conformation similar to Mtb-SigJ (PDB ID: 5XE7) that can readily interact with the promoter. A) Structural superposition of σ2 and σ4 with previously determined structures of the −10 promoter/ σ 2 (PDB ID: 4LUP) and −35 promoter/σ4 (PDB ID: 2H27) complexes (36, 38).B) The comparative Root Mean Square Fluctuation (RMSF) plot of RpoE10 and Its mutant forms. The critical residue positions showing distinct RMSF peaks are indicated by numbers 1-9, and these residues are mapped (in black color) onto the structure of the RpoE10 model.