1ECW | pdb_00001ecw

CRYSTAL STRUCTURE OF SIMIAN IMMUNODEFICIENCY VIRUS MATRIX ANTIGEN (SIV MA) AT 293K.

• PDB DOI: https://doi.org/10.2210/pdb1ECW/pdb

• Classification: VIRAL PROTEIN
• Organism(s): Simian immunodeficiency virus
• Expression System: unidentified baculovirus
• Mutation(s): No 


• Deposited: 2000-01-26 Released: 2000-02-16 
• Deposition Author(s): Rao, Z., Belyaev, A., Fry, E., Roy, P., Jones, I.M., Stuart, D.I.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.20 Å
• R-Value Work: 
  0.164 (Depositor) 

Literature

Crystal structure of SIV matrix antigen and implications for virus assembly.

Rao, Z., Belyaev, A.S., Fry, E., Roy, P., Jones, I.M., Stuart, D.I.

(1995) Nature 378: 743-747

• PubMed: 7501025 
• DOI: https://doi.org/10.1038/378743a0
• Primary Citation Related Structures: 
  1ECW, 1ED1


• PubMed Abstract: 
  

  Simian immunodeficiency virus (SIV) is closely related to human immunodeficiency virus (HIV), their matrix antigens (MAs) sharing some 50% sequence identity. MA is a component of Pr55Gag, the sole protein required for assembly of the virion shell. MA targets Pr55 to the plasma membrane, and facilitates incorporation of the virus envelope protein and assembly of the Pr55Gag shell. Cleavage of Pr55 by the viral protease produces the mature protein of relative molecular mass 17-18K, which underlies the host-derived membrane and is important in both virus entry and nuclear localization of the virion core. Here we report the crystal structure of SIV MA. The molecule forms a trimer consistent with oligomerization in vitro, the observed virion architecture, and various biological properties of MA.

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Organizational Affiliation: 
• Laboratory of Molecular Biophysics, Oxford, UK.

Biological Assembly 1  

Global Symmetry: Cyclic - C3  (Explore in 3D)
Global Stoichiometry: Homo 3-mer - A3 

Biological assembly 1 assigned by authors.

Macromolecule Content 

• Total Structure Weight: 14.98 kDa 
• Atom Count: 972 
• Modeled Residue Count: 114 
• Deposited Residue Count: 135 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
GAG POLYPROTEIN	A	135	Simian immunodeficiency virus	Mutation(s): 0  Gene Names: GAG
UniProt
Find proteins for P05897 (Simian immunodeficiency virus (isolate Mm251)) Explore P05897  Go to UniProtKB:  P05897

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
IPA	B [auth A]	ISOPROPYL ALCOHOL C3 H8 O KFZMGEQAYNKOFK-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.20 Å
• R-Value Work:  0.164 (Depositor) 

Space Group: H 3

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 114.9	α = 90
b = 114.9	β = 90
c = 32.3	γ = 120

Software Package:

Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
MLPHARE	phasing
X-PLOR	refinement

Structure Validation

Entry History 

Deposition Data

• Released Date: 2000-02-16 
Deposition Author(s): Rao, Z., Belyaev, A., Fry, E., Roy, P., Jones, I.M., Stuart, D.I.

Revision History  

• Version 1.0: 2000-02-16
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2024-02-07
  Changes: Data collection, Database references, Derived calculations