Fig. 3: Structural and functional differences between IPTG-LacI and DNA-LacI.

A Diagrams on the right are cross-sectioned according to the schematic on the left. Secondary structure elements are labeled according to Fig. 2C, top. Purple: less exchange in DNA-LacI; teal: less exchange in IPTG-LacI. B LacI models colored by mutational phenotype classes: IS (constitutive repression) and I− (constitutive expression)19. The table summarizes mutational phenotype data as percentages of residues in differentially rigidified regions observed in HDX/MS experiments. PDB ID: 2P9H (IPTG-bound LacI core domain).