2R2J

crystal structure of human ERp44

• PDB DOI: https://doi.org/10.2210/pdb2R2J/pdb

• Classification: CHAPERONE
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2007-08-25 Released: 2008-07-08 
• Deposition Author(s): Wang, L.K., Li, S.J., Sun, F., Wang, C.C.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.60 Å
• R-Value Free: 0.263 
• R-Value Work: 0.217 
• R-Value Observed: 0.219 

Literature

Crystal structure of human ERp44 shows a dynamic functional modulation by its carboxy-terminal tail.

Wang, L.K., Wang, L., Vavassori, S., Li, S.J., Ke, H., Anelli, T., Degano, M., Ronzoni, R., Sitia, R., Sun, F., Wang, C.C.

(2008) EMBO Rep 

• PubMed: 18552768 
• DOI: https://doi.org/10.1038/embor.2008.88
• Primary Citation of Related Structures:  
  2R2J


• PubMed Abstract: 
  

  ERp44 mediates thiol-dependent retention in the early secretory pathway, forming mixed disulphides with substrate proteins through its conserved CRFS motif. Here, we present its crystal structure at a resolution of 2.6 A. Three thioredoxin domains-a, b and b'-are arranged in a clover-like structure. A flexible carboxy-terminal tail turns back to the b' and a domains, shielding a hydrophobic pocket in domain b' and a hydrophobic patch around the CRFS motif in domain a. Mutational and functional studies indicate that the C-terminal tail gates the CRFS area and the adjacent hydrophobic pocket, dynamically regulating protein quality control.

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Organizational Affiliation: 

National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.

Biological Assembly 1  

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

Biological assembly 1 assigned by authors.

Biological Assembly 2  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 2 generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 44.77 kDa 
• Atom Count: 2,827 
• Modelled Residue Count: 328 
• Deposited Residue Count: 382 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Thioredoxin domain-containing protein 4	A	382	Homo sapiens	Mutation(s): 0  Gene Names: TXNDC4, ERP44, KIAA0573
UniProt & NIH Common Fund Data Resources
Find proteins for Q9BS26 (Homo sapiens) Explore Q9BS26  Go to UniProtKB:  Q9BS26
PHAROS:  Q9BS26 GTEx:  ENSG00000023318

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SIN	B [auth A]	SUCCINIC ACID C4 H6 O4 KDYFGRWQOYBRFD-UHFFFAOYSA-N
FMT	C [auth A], D [auth A]	FORMIC ACID C H2 O2 BDAGIHXWWSANSR-UHFFFAOYSA-N

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
MSE	A	L-PEPTIDE LINKING	C5 H11 N O2 Se		MET

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.60 Å
• R-Value Free: 0.263 
• R-Value Work: 0.217 
• R-Value Observed: 0.219 
• Space Group: P 3₁ 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 83.501	α = 90
b = 83.501	β = 90
c = 123.137	γ = 120

Software Package:

Software Name	Purpose
REFMAC	refinement
HKL-2000	data collection
HKL-2000	data reduction
HKL-2000	data scaling
SOLVE	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2008-07-08 
Deposition Author(s): Wang, L.K., Li, S.J., Sun, F., Wang, C.C.

Revision History  

• Version 1.0: 2008-07-08
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Advisory, Version format compliance