1MG1

HTLV-1 GP21 ECTODOMAIN/MALTOSE-BINDING PROTEIN CHIMERA


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.50 Å
  • R-Value Free: 0.305 
  • R-Value Work: 0.223 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Crystal structure of human T cell leukemia virus type 1 gp21 ectodomain crystallized as a maltose-binding protein chimera reveals structural evolution of retroviral transmembrane proteins.

Kobe, B.Center, R.J.Kemp, B.E.Poumbourios, P.

(1999) Proc Natl Acad Sci U S A 96: 4319-4324

  • DOI: 10.1073/pnas.96.8.4319
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • Retroviral entry into cells depends on envelope glycoproteins, whereby receptor binding to the surface-exposed subunit triggers membrane fusion by the transmembrane protein (TM) subunit. We determined the crystal structure at 2.5-A resolution of the ...

    Retroviral entry into cells depends on envelope glycoproteins, whereby receptor binding to the surface-exposed subunit triggers membrane fusion by the transmembrane protein (TM) subunit. We determined the crystal structure at 2.5-A resolution of the ectodomain of gp21, the TM from human T cell leukemia virus type 1. The gp21 fragment was crystallized as a maltose-binding protein chimera, and the maltose-binding protein domain was used to solve the initial phases by the method of molecular replacement. The structure of gp21 comprises an N-terminal trimeric coiled coil, an adjacent disulfide-bonded loop that stabilizes a chain reversal, and a C-terminal sequence structurally distinct from HIV type 1/simian immunodeficiency virus gp41 that packs against the coil in an extended antiparallel fashion. Comparison of the gp21 structure with the structures of other retroviral TMs contrasts the conserved nature of the coiled coil-forming region and adjacent disulfide-bonded loop with the variable nature of the C-terminal ectodomain segment. The structure points to these features having evolved to enable the dual roles of retroviral TMs: conserved fusion function and an ability to anchor diverse surface-exposed subunit structures to the virion envelope and infected cell surface. The structure of gp21 implies that the N-terminal fusion peptide is in close proximity to the C-terminal transmembrane domain and likely represents a postfusion conformation.


    Related Citations: 
    • Crystallization of a Trimeric Human T Cell Leukemia Virus Type 1 Gp21 Ectodomain Fragment as a Chimera with Maltose-Binding Protein
      Center, R.J., Kobe, B., Wilson, K.A., Teh, T., Howlett, G.J., Kemp, B.E., Poumbourios, P.
      (1998) Protein Sci 7: 1612

    Organizational Affiliation

    St. Vincent's Institute of Medical Research, 41 Victoria Parade, Fitzroy, Victoria 3065, Australia.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PROTEIN (HTLV-1 GP21 ECTODOMAIN/MALTOSE-BINDING PROTEIN CHIMERA)
A
450Human T-cell leukemia virus type IMutation(s): 0 
Find proteins for P0AEX9 (Escherichia coli (strain K12))
Go to UniProtKB:  P0AEX9
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MAL
Query on MAL

Download CCD File 
A
MALTOSE
C12 H22 O11
GUBGYTABKSRVRQ-ASMJPISFSA-N
 Ligand Interaction
CL
Query on CL

Download CCD File 
A
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.50 Å
  • R-Value Free: 0.305 
  • R-Value Work: 0.223 
  • Space Group: H 3
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 102.947α = 90
b = 102.947β = 90
c = 118.005γ = 120
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
X-PLORmodel building
X-PLORrefinement
X-PLORphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1999-04-06
    Type: Initial release
  • Version 1.1: 2008-04-26
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Derived calculations, Version format compliance