Interaction of water molecules in non-identical protein structures

Abstract

The interaction of the protein atoms with the surrounding water oxygen atoms has been computed for 392 protein chains from 369 protein structures belonging to 90% non-homologous high resolution (˂ = 1.5 Å) protein structures with a crystallographic R-factor ≤ 20%. The percentage composition of the polar atoms is found to be 36.3%. An average of

82.55% of water oxygen atoms are found to be in the primary hydration shell and 15.12% in the secondary hydration shell. The average percentage of interactions of water oxygen atoms with the polar atoms of the main chain and side chain are 54% and 46%, respectively. The interaction of the acidic residues, aspartate and glutamate, with the water oxygen atoms is

more when compared to that of the other residues.