**3. Strategies for All Enzyme Stabilization**

Enzyme stability involves a balance between intramolecular interactions of functional groups and their interaction with the protein environment. Water, as many protein natural solvent, plays a key role in enzyme stability by controlling the hydration shell structure and dynamics and by providing required plasticity for activity [28]. As a direct consequence, many stabilization strategies target water activity in the environment of the enzyme or inside the protein moiety, with the main objective of decreasing the enzyme motion (Figure 2). However, this enhanced stability should not be achieved at the expense of activity, so a delicate balance must be maintained between rigidification and sufficient plasticity controlled by water. As another mere general rule, stabilization over one stress tends to enhance stability against another stress.

**Figure 2.** Strategies for all enzyme stabilization.
