1M8N

Choristoneura Fumiferana (Spruce Budworm) Antifreeze Protein Isoform 501


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.45 Å
  • R-Value Free: 0.291 
  • R-Value Work: 0.221 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

A beta-helical antifreeze protein isoform with increased activity: structural and functional insights

Leinala, E.K.Davies, P.L.Doucet, D.Tyshenko, M.G.Walker, V.K.Jia, Z.

(2002) J.Biol.Chem. 277: 33349-33352

  • DOI: 10.1074/jbc.M205575200

  • PubMed Abstract: 
  • The insect spruce budworm (Choristoneura fumiferana)(Cf) produces a number of isoforms of its highly active antifreeze protein (CfAFP). Although most of the CfAFP isoforms are in the 9-kDa range, isoforms containing a 30- or 31-amino acid insertion h ...

    The insect spruce budworm (Choristoneura fumiferana)(Cf) produces a number of isoforms of its highly active antifreeze protein (CfAFP). Although most of the CfAFP isoforms are in the 9-kDa range, isoforms containing a 30- or 31-amino acid insertion have also been identified. Here we describe the functional and structural analysis of a selected long isoform, CfAFP-501. X-ray crystal structure determination reveals that the 31-amino acid insertion found in CfAFP-501 forms two additional loops within its highly regular beta-helical structure. This effectively extends the area of the two-dimensional Thr array and ice-binding surface of the protein. The larger isoform has 3 times the thermal hysteresis activity of the 9-kDa CfAFP-337. As well, a deletion of the 31-amino acid insertion within CfAFP-501 to form CfAFP-501-Delta-2-loop, results in a protein with reduced activity similar to the shorter CfAFP isoforms. Thus, the enhanced antifreeze activity of CfAFP-501 is directly correlated to the length of its beta-helical structure and hence the size of its ice-binding face.


    Organizational Affiliation

    Departments of Biochemistry and Biology, Queen's University, Kingston, Ontario, K7L 3N6 Canada.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Antifreeze protein isoform 501
A, B, C, D
121Choristoneura fumiferanaN/A
Find proteins for Q9GSA6 (Choristoneura fumiferana)
Go to UniProtKB:  Q9GSA6
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.45 Å
  • R-Value Free: 0.291 
  • R-Value Work: 0.221 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 43.900α = 90.00
b = 57.400β = 92.10
c = 70.130γ = 90.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
DENZOdata reduction
EPMRphasing
CNSrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2002-09-18
    Type: Initial release
  • Version 1.1: 2008-04-28
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2018-01-24
    Type: Database references