1EPT

REFINED 1.8 ANGSTROMS RESOLUTION CRYSTAL STRUCTURE OF PORCINE EPSILON-TRYPSIN

• PDB DOI: https://doi.org/10.2210/pdb1EPT/pdb

• Classification: HYDROLASE (SERINE PROTEASE)
• Organism(s): Sus scrofa
• Mutation(s): No 


• Deposited: 1994-06-07 Released: 1995-02-07 
• Deposition Author(s): Huang, Q., Wang, Z., Li, Y., Liu, S., Tang, Y.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.80 Å
• R-Value Work: 0.184 
• R-Value Observed: 0.184 

Literature

Refined 1.8 A resolution crystal structure of the porcine epsilon-trypsin.

Huang, Q., Wang, Z., Li, Y., Liu, S., Tang, Y.

(1994) Biochim Biophys Acta 1209: 77-82

• PubMed: 7947985 
• DOI: https://doi.org/10.1016/0167-4838(94)90139-2
• Primary Citation of Related Structures:  
  1EPT


• PubMed Abstract: 
  

  Porcine epsilon-trypsin is a three-chain inactivated trypsin from the limited autolysis of porcine beta-trypsin. It is cleaved at positions Lys60-Ser61 and Lys145-Ser146. The crystal structure has been determined by using the molecular replacement method, and refined at 1.8 A resolution. The R-value of final model is 0.184. Comparison with the electron density map of porcine beta-trypsin (PTRY) in complex (BBIT), and with that of native bovine beta-trypsin (HTNA), revealed no obvious changes except at the autolysis positions, and no changes at the active center were observed. The autolysis at positions Lys60-Ser61 and Lys145-Ser146 does not affect the conformation of His-57 in the active center and therefore cannot explain for a loss in porcine epsilon-trypsin activity.

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Organizational Affiliation: 

Department of Chemistry, Peking University, Beijing, China.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 3-mer - A1B1C1 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 23.57 kDa 
• Atom Count: 1,717 
• Modelled Residue Count: 223 
• Deposited Residue Count: 223 
• Unique protein chains: 3

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PORCINE E-TRYPSIN	A	43	Sus scrofa	Mutation(s): 0  EC: 3.4.21.4
UniProt
Find proteins for P00761 (Sus scrofa) Explore P00761  Go to UniProtKB:  P00761

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
PORCINE E-TRYPSIN	B	82	Sus scrofa	Mutation(s): 0  EC: 3.4.21.4
UniProt
Find proteins for P00761 (Sus scrofa) Explore P00761  Go to UniProtKB:  P00761

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details	Image
PORCINE E-TRYPSIN	C	98	Sus scrofa	Mutation(s): 0  EC: 3.4.21.4
UniProt
Find proteins for P00761 (Sus scrofa) Explore P00761  Go to UniProtKB:  P00761

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
CA	D [auth B]	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.80 Å
• R-Value Work: 0.184 
• R-Value Observed: 0.184 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 76.9	α = 90
b = 53.4	β = 90
c = 46.6	γ = 90

Software Package:

Software Name	Purpose
X-PLOR	model building
X-PLOR	refinement
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 1995-02-07 
Deposition Author(s): Huang, Q., Wang, Z., Li, Y., Liu, S., Tang, Y.

Revision History  

• Version 1.0: 1995-02-07
  Type: Initial release
  
• Version 1.1: 2008-03-24
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2024-06-05
  Changes: Data collection, Database references, Derived calculations, Other