Figure 1

Distribution of the water molecules near the protein surface predicted from high resolution structures (adapted from ref. 30). The relative number of water molecules versus distance is plotted for a halophilic glucose dehydrogenase enzyme active at low water activity (red) [30] and for non-halophilic enzymes (black). Multiple hydration layers may surround extremophilic proteins as a result of their ability to bind more tightly to water than non-extremophilic proteins.