1FIO | pdb_00001fio

CRYSTAL STRUCTURE OF YEAST T-SNARE PROTEIN SSO1

• PDB DOI: https://doi.org/10.2210/pdb1FIO/pdb

• Classification: MEMBRANE PROTEIN
• Organism(s): Saccharomyces cerevisiae
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2000-08-04 Released: 2000-10-11 
• Deposition Author(s): Munson, M., Chen, X., Cocina, A.E., Schultz, S.M., Hughson, F.M.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.10 Å
• R-Value Free: 
  0.265 (Depositor) 
• R-Value Work: 
  0.219 (Depositor), 0.241 (DCC) 
• R-Value Observed: 
  0.221 (Depositor) 

Literature

Interactions within the yeast t-SNARE Sso1p that control SNARE complex assembly.

Munson, M., Chen, X., Cocina, A.E., Schultz, S.M., Hughson, F.M.

(2000) Nat Struct Biol 7: 894-902

• PubMed: 11017200 
• DOI: https://doi.org/10.1038/79659
• Primary Citation Related Structures: 
  1FIO


• PubMed Abstract: 
  

  In the eukaryotic secretory and endocytic pathways, transport vesicles shuttle cargo among intracellular organelles and to and from the plasma membrane. Cargo delivery entails fusion of the transport vesicle with its target, a process thought to be mediated by membrane bridging SNARE protein complexes. Temporal and spatial control of intracellular trafficking depends in part on regulating the assembly of these complexes. In vitro, SNARE assembly is inhibited by the closed conformation adopted by the syntaxin family of SNAREs. To visualize this closed conformation directly, the X-ray crystal structure of a yeast syntaxin, Sso1p, has been determined and refined to 2.1 A resolution. Mutants designed to destabilize the closed conformation exhibit accelerated rates of SNARE assembly. Our results provide insight into the mechanism of SNARE assembly and its intramolecular and intermolecular regulation.

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Organizational Affiliation: 
• Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544, USA.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content 

• Total Structure Weight: 22.93 kDa 
• Atom Count: 1,708 
• Modeled Residue Count: 190 
• Deposited Residue Count: 196 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
SSO1 PROTEIN	A	196	Saccharomyces cerevisiae	Mutation(s): 0
UniProt
Find proteins for P32867 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c)) Explore P32867  Go to UniProtKB:  P32867

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
ZN	B [auth A], C [auth A]	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.10 Å
• R-Value Free:  0.265 (Depositor) 
• R-Value Work:  0.219 (Depositor), 0.241 (DCC) 
• R-Value Observed: 0.221 (Depositor) 

Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 42.517	α = 90
b = 49.855	β = 90
c = 113.84	γ = 90

Software Package:

Software Name	Purpose
MLPHARE	phasing
CNS	refinement
DENZO	data reduction
SCALEPACK	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2000-10-11 
Deposition Author(s): Munson, M., Chen, X., Cocina, A.E., Schultz, S.M., Hughson, F.M.

Revision History  

• Version 1.0: 2000-10-11
  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: 2022-12-21
  Changes: Database references, Derived calculations
• Version 1.4: 2024-05-22
  Changes: Data collection