A solvation shell or solvation sheath is the solvent interface of any chemical compound or biomolecule that constitutes the solute. When the solvent is water it is often referred to as a hydration shell or hydration sphere. The number of solvent molecules surrounding each unit of solute is called the hydration number of the solute. The hydration shell (also sometimes called hydration layer) that forms around proteins is of particular importance in biochemistry. This interaction of the protein surface with the surrounding water is often referred to as protein hydration and is fundamental to the activity of the protein. The hydration layer around a protein has been found to have dynamics distinct from the bulk water to a distance of 1 nm. The duration of contact of a specific water molecule with the protein surface may be in the subnanosecond range while molecular dynamics simulations suggest the time water spends in the hydration shell before mixing with the outside bulk water could be in the femtosecond to picosecond range, and that near features conventionally regarded as attractive to water, such as hydrogen bond donors, the water molecules are actually relatively weakly bound and are easily displaced. At high resolution, scientists can clearly determine the hydration sphere surrounding proteins. Here you have an example of how the water molecules surround a protein molecule. This is a 1.6 A resolution crystal structure of a beta-lactamase dimer from Pseudomonas aeruginosa (PDB code: 7B3U)
#molecularart ... #immolecular ... #water ... #hydration ... #sphere ... #contact ... #crystalstructure ... #betalactamase ... #pseudomonas ... #xray
Beta-lactamase and water hydration sphere rendered with @proteinimaging and depicted with @corelphotopaint
#molecularart ... #immolecular ... #water ... #hydration ... #sphere ... #contact ... #crystalstructure ... #betalactamase ... #pseudomonas ... #xray
Beta-lactamase and water hydration sphere rendered with @proteinimaging and depicted with @corelphotopaint
