1LSM

THERMAL STABILITY DETERMINANTS OF CHICKEN EGG-WHITE LYSOZYME CORE MUTANTS: HYDROPHOBICITY, PACKING VOLUME AND CONSERVED BURIED WATER MOLECULES


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Thermal stability determinants of chicken egg-white lysozyme core mutants: hydrophobicity, packing volume, and conserved buried water molecules.

Shih, P.Holland, D.R.Kirsch, J.F.

(1995) Protein Sci. 4: 2050-2062

  • DOI: 10.1002/pro.5560041010
  • Primary Citation of Related Structures:  1LSN

  • PubMed Abstract: 
  • A series of 24 mutants was made in the buried core of chicken lysozyme at positions 40, 55, and 91. The midpoint temperature of thermal denaturation transition (Tm) values of these core constructs range from 60.9 to 77.3 degrees C, extending an earli ...

    A series of 24 mutants was made in the buried core of chicken lysozyme at positions 40, 55, and 91. The midpoint temperature of thermal denaturation transition (Tm) values of these core constructs range from 60.9 to 77.3 degrees C, extending an earlier, more limited investigation on thermostability. The Tm values of variants containing conservative replacements for the wild type (WT) (Thr 40-Ile 55-Ser 91) triplet are linearly correlated with hydrophobicity (r = 0.81) and, to a lesser degree, with combined side-chain volume (r = 0.75). The X-ray structures of the S91A (1.9 A) and I55L/S91T/D101S (1.7 A) mutants are presented. The former amino acid change is found in duck and mammalian lysozymes, and the latter contains the most thermostable core triplet. A network of four conserved, buried water molecules is associated with the core. It is postulated that these water molecules significantly influence the mutational tolerance at the individual triplet positions. The pH dependence of Tm for the S91D mutant was compared with that of WT enzyme. The pKa of S91D is 1.2 units higher in the native than in the denatured state, corresponding to delta delta G298 = 1.7 kcal/mol. This is a low value for charge burial and likely reflects the moderating influence of the buried water molecules or a conformational change. Thermal and chemical denaturation and far UV CD spectroscopy were used to characterize the in vitro properties of I55T. This variant, which buries a hydroxyl group, has similar properties to those of the human amyloidogenic variant I56T.


    Related Citations: 
    • Ancestral Lysozymes Reconstructed, Neutrality Tested, and Thermostability Linked to Hydrocarbon Packing
      Malcolm, B.A.,Wilson, K.P.,Matthews, B.W.,Kirsch, J.F.,Wilson, A.C.
      (1990) Nature 344: 86
    • Structural and Thermodynamic Analysis of Compensating Mutations within the Core of Chicken Egg White Lysozyme
      Wilson, K.P.,Malcolm, B.A.,Matthews, B.W.
      (1992) J.Biol.Chem. 267: 10842


    Organizational Affiliation

    Department of Chemistry, University of California, Berkeley 94720, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
HEN EGG WHITE LYSOZYME
A
129Gallus gallusGene Names: LYZ
EC: 3.2.1.17
Find proteins for P00698 (Gallus gallus)
Go to Gene View: LYZ
Go to UniProtKB:  P00698
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • Space Group: P 43 21 2
Unit Cell:
Length (Å)Angle (°)
a = 79.080α = 90.00
b = 79.080β = 90.00
c = 37.800γ = 90.00
Software Package:
Software NamePurpose
TNTrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1994-11-30
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance