1BSQ

STRUCTURAL AND FUNCTIONAL CONSEQUENCES OF POINT MUTATIONS OF VARIANTS A AND B OF BOVINE BETA-LACTOGLOBULIN


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.22 Å
  • R-Value Free: 0.286 
  • R-Value Work: 0.239 
  • R-Value Observed: 0.239 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Functional implications of structural differences between variants A and B of bovine beta-lactoglobulin.

Qin, B.Y.Bewley, M.C.Creamer, L.K.Baker, E.N.Jameson, G.B.

(1999) Protein Sci 8: 75-83

  • DOI: https://doi.org/10.1110/ps.8.1.75
  • Primary Citation of Related Structures:  
    1BSQ

  • PubMed Abstract: 

    The structure of the trigonal crystal form of bovine beta-lactoglobulin variant B at pH 7.1 has been determined by X-ray diffraction methods at a resolution of 2.22 A and refined to values for R and Rfree of 0.239 and 0.286, respectively. By comparison with the structure of the trigonal crystal form of bovine beta-lactoglobulin variant A at pH 7.1, which was determined previously [Qin BY et al., 1998, Biochemistry 37:14014-14023], the structural consequences of the sequence differences D64G and V118A of variants A and B, respectively, have been investigated. Only minor differences in the core calyx structure occur. In the vicinity of the mutation site D64G on loop CD (residues 61-67), there are small changes in main-chain conformation, whereas the substitution V118A on beta-strand H is unaccompanied by changes in the surrounding structure, thereby creating a void volume and weakened hydrophobic interactions with a consequent loss of thermal stability relative to variant A. A conformational difference is found for the loop EF, implicated in the pH-dependent conformational change known as the Tanford transition, but it is not clear whether this reflects differences intrinsic to the variants in solution or differences in crystallization.


  • Organizational Affiliation

    Centre for Structural Biology, Institute of Fundamental Sciences, Massey University, Palmerston North, New Zealand.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
PROTEIN (BETA-LACTOGLOBULIN)162Bos taurusMutation(s): 0 
UniProt
Find proteins for P02754 (Bos taurus)
Explore P02754 
Go to UniProtKB:  P02754
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP02754
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.22 Å
  • R-Value Free: 0.286 
  • R-Value Work: 0.239 
  • R-Value Observed: 0.239 
  • Space Group: P 32 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 54.231α = 90
b = 54.231β = 90
c = 113.019γ = 120
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
AMoREphasing
X-PLORrefinement

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1998-09-02
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance