Figure 3

Examples of residue substitutions decreasing the area of the conserved hydrophobic contacts. A) Superposition of two equivalent CHCs in the halophilic glucose dehydrogenase from Haloferax mediterranei (color orange, PDB ID: 2B5W) and its counterpart from Sulfolobus solfataricus (color light blue, PDB ID: 2CD9). Secondary structures are represented as cartoon and residues involved in the apolar contact are shown as sticks models. Halophilic Val30 replaces Ile31 of the mesophile. The other contacting residue, Leu, is conserved in both proteins. B) Superposition of two equivalent CHCs in the halophilic malate dehydrogenase from Haloarcula marismortui (color magenta, PDB ID: 2J5K) and its mesophilic counterpart from Clostridium thermocellum (color cyan, PDB ID: 1Y6J). Secondary structures are represented as cartoon and residues involved in the apolar contact are shown as sticks models. Halophilic Val27 and Val94 replace Ile13 and Ile78 of the counterpart, respectively.