1ckh

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spinqualitylabelsall models 1ckh, resolution 2.Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

T70V MUTANT HUMAN LYSOZYME

Contents 1 Overview 2 Disease 3 About this Structure 4 Reference

Overview

In globular proteins, there are intermolecular hydrogen bonds between, protein and water molecules, and between water molecules, which are bound, with the proteins, in addition to intramolecular hydrogen bonds. To, estimate the contribution of these hydrogen bonds to the conformational, stability of a protein, the thermodynamic parameters for denaturation and, the crystal structures of five Thr to Val and five Thr to Ala mutant human, lysozymes were determined. The denaturation Gibbs energy (DeltaG) of Thr, to Val and Thr to Ala mutant proteins was changed from 4.0 to -5.6 kJ/mol, and from 1.6 to -6.3 kJ/mol, respectively, compared with that of the, wild-type protein. The contribution of hydrogen bonds to the stability, (DeltaDeltaG(HB)) of the Thr and other mutant human lysozymes previously, reported was extracted from the observed stability changes (DeltaDeltaG), with correction for changes in hydrophobicity and side chain, conformational entropy between the wild-type and mutant structures. The, estimation of the DeltaDeltaG(HB) values of all mutant proteins after, removal of hydrogen bonds, including protein-water hydrogen bonds, indicates a favorable contribution of the intra- and intermolecular, hydrogen bonds to the protein stability. The net contribution of an, intramolecular hydrogen bond (DeltaG(HB[pp])), an intermolecular one, between protein and ordered water molecules (DeltaG(HB[pw])), and an, intermolecular one between ordered water molecules (DeltaG(HB[ww])) could, be estimated to be 8. 5, 5.2, and 5.0 kJ/mol, respectively, for a 3 A long, hydrogen bond. This result shows the different contributions to protein, stability of intra- and intermolecular hydrogen bonds. The entropic cost, due to the introduction of a water molecule (DeltaG(H)()2(O)) could be, also estimated to be about 8 kJ/mol.

Disease

Known diseases associated with this structure: Amyloidosis, renal OMIM:[153450], Microphthalmia, syndromic 1 OMIM:[309800]

About this Structure

1CKH is a Single protein structure of sequence from Homo sapiens. Active as Lysozyme, with EC number 3.2.1.17 Full crystallographic information is available from OCA.

Reference

Contribution of intra- and intermolecular hydrogen bonds to the conformational stability of human lysozyme(,)., Takano K, Yamagata Y, Funahashi J, Hioki Y, Kuramitsu S, Yutani K, Biochemistry. 1999 Sep 28;38(39):12698-708. PMID:10504240

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