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The water structure in despentapeptide (B26-B30) insulin crystal is presented in this paper. Ac-cording to inspection of the final F_0-extended (2F_0-F_c) Fourier map, 81 water molecules (about twothirds of solvent) with electron density greater tLan 0.4 e/A~3 are included in the water model to bediscussed. In a hydrogen bond length range of 2.4--3.2 A, 51 water molecules, that is, 63% of thetotal 81, are hydrogen bonded to protein, of which 12 link the adjacent protein molecules through one-water bridges and more through two-water bridges. There is a tight water network in a long crevice be-tween protein molecules; two Cd atoms, like two piles, prop up the network through three water molecules(Cd ligands) at either end of the network, indicating that Cd ions and water networks play an importantrole in close packing of protein molecules in the crystal.
Ac-cording to inspection of the final F_0-extended (2F_0-F_c) Fourier map, 81 water molecules (about twothirds of solvent) with electron density greater tLan 0.4 e / A ~ 3 are included in the water model to bediscussed. In a hydrogen bond length range of 2.4--3.2 A, 51 water molecules, that is, 63% of the total 81, are hydrogen bonded to protein, of which 12 link the adjacent protein molecules through one-water bridges and more through two-water bridges. There is a tight water network in a long crevice be-tween protein molecules; two Cd atoms, like two piles, prop up the network through three water molecules (Cd ligands) at either end of the network, indicating that Cd ions and water networks play an importantrole in close packing of protein molecules in the crystal.