4CPA

REFINED CRYSTAL STRUCTURE OF THE POTATO INHIBITOR COMPLEX OF CARBOXYPEPTIDASE A AT 2.5 ANGSTROMS RESOLUTION

• PDB DOI: https://doi.org/10.2210/pdb4CPA/pdb
• Entry: 4CPA supersedes: 1CPA

• Classification: HYDROLASE (C-TERMINAL PEPTIDASE)
• Organism(s): Bos taurus, Solanum tuberosum
• Mutation(s): No 


• Deposited: 1982-03-24 Released: 1982-07-29 
• Deposition Author(s): Lipscomb, W.N., Rees, D.C.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å

Literature

Refined crystal structure of the potato inhibitor complex of carboxypeptidase A at 2.5 A resolution.

Rees, D.C., Lipscomb, W.N.

(1982) J Mol Biol 160: 475-498

• PubMed: 7154070 
• DOI: https://doi.org/10.1016/0022-2836(82)90309-6
• Primary Citation of Related Structures:  
  4CPA

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B1 

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

Biological Assembly 2  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B1 

Biological assembly 2 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 77.53 kDa 
• Atom Count: 5,456 
• Modelled Residue Count: 688 
• Deposited Residue Count: 690 
• Unique protein chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
CARBOXYPEPTIDASE A	A, C [auth B]	307	Bos taurus	Mutation(s): 0  EC: 3.4.17.1
UniProt
Find proteins for P00730 (Bos taurus) Explore P00730  Go to UniProtKB:  P00730

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
METALLOCARBOXYPEPTIDASE INHIBITOR	B [auth I], D [auth J]	38	Solanum tuberosum	Mutation(s): 0
UniProt
Find proteins for P01075 (Solanum tuberosum) Explore P01075  Go to UniProtKB:  P01075

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
GLY	E [auth A], G [auth B]	GLYCINE C2 H5 N O2 DHMQDGOQFOQNFH-UHFFFAOYSA-N
ZN	F [auth I], H [auth J]	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
GLY	PDBBind:  4CPA	Kd: 5 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• Space Group: P 3₂

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 53.45	α = 90
b = 53.45	β = 90
c = 218.5	γ = 120

Software Package:

Software Name	Purpose
PROLSQ	refinement

Structure Validation

Entry History 

Deposition Data

• Released Date: 1982-07-29 
Deposition Author(s): Lipscomb, W.N., Rees, D.C.
• This entry supersedes: 1CPA

Revision History  

• Version 1.0: 1982-07-29
  Type: Initial release
  
• Version 1.1: 2008-03-25
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Advisory, Version format compliance
• Version 1.3: 2017-11-29
  Changes: Derived calculations, Other
• Version 2.0: 2023-09-27
  Type: Remediation
  Changes: Advisory, Atomic model, Data collection, Database references, Derived calculations, Other, Refinement description
• Version 2.1: 2024-10-16
  Changes: Structure summary