Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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

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

Macromolecule Content

• Total Structure Weight: 105.98 kDa 
• Atom Count: 7992 
• Modelled Residue Count: 875 
• Deposited Residue Count: 888 
• Unique protein chains: 1

4KX7

Crystal structure of human aminopeptidase A

• DOI: 10.2210/pdb4KX7/pdb

• Classification: HYDROLASE
• Organism(s): Homo sapiens
• Expression System: Spodoptera frugiperda
• Mutation(s): Yes 


• Deposited: 2013-05-24 Released: 2013-07-31 
• Deposition Author(s): Yang, Y., Liu, C., Lin, Y.Y., Li, F.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.15 Å
• R-Value Free: 0.218 
• R-Value Work: 0.173 
• R-Value Observed: 0.175 

Literature

Structural insights into central hypertension regulation by human aminopeptidase a.

Yang, Y., Liu, C., Lin, Y.L., Li, F.

(2013) J Biol Chem 288: 25638-25645

• PubMed: 23888046 
• DOI: 10.1074/jbc.M113.494955
• Primary Citation of Related Structures:  
  4KX9, 4KX7, 4KX8, 4KXA, 4KXB, 4KXC, 4KXD


• PubMed Abstract: 
  

Hypertension is regulated through both the central and systemic renin-angiotensin systems. In the central renin-angiotensin system, zinc-dependent aminopeptidase A (APA) up-regulates blood pressure by specifically cleaving the N-terminal aspartate, but not the adjacent arginine, from angiotensin II, a process facilitated by calcium. Here, we determined the crystal structures of human APA and its complexes with different ligands and identified a calcium-binding site in the S1 pocket of APA. Without calcium, the S1 pocket can bind both acidic and basic residues through formation of salt bridges with the charged side chains. In the presence of calcium, the binding of acidic residues is enhanced as they ligate the cation, whereas the binding of basic residues is no longer favorable due to charge repulsion. Of the peptidomimetic inhibitors of APA, amastatin has higher potency than bestatin by fitting better in the S1 pocket and interacting additionally with the S3' subsite. These results explain the calcium-modulated substrate specificity of APA in central hypertension regulation and can guide the design and development of brain-targeting antihypertensive APA inhibitors.

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Organizational Affiliation: 

Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota 55455, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Glutamyl aminopeptidase	A	888	Homo sapiens	Mutation(s): 2  Gene Names: ENPEP EC: 3.4.11.7
UniProt & NIH Common Fund Data Resources
Find proteins for Q07075 (Homo sapiens) Explore Q07075  Go to UniProtKB:  Q07075
PHAROS:  Q07075 GTEx:  ENSG00000138792

Oligosaccharides

Help

Entity ID: 2
Molecule	Chains	Chain Length	2D Diagram	Glycosylation
2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose	B, C, F	2		N-Glycosylation

Entity ID: 3
Molecule	Chains	Chain Length	2D Diagram	Glycosylation
2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose	D, E	3		N-Glycosylation

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
NAG	H [auth A], I [auth A], J [auth A]	2-acetamido-2-deoxy-beta-D-glucopyranose C8 H15 N O6 OVRNDRQMDRJTHS-FMDGEEDCSA-N
ZN	G [auth A]	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N

Biologically Interesting Molecules (External Reference) 1 Unique

Entity ID: 3
ID	Chains	Name	Type/Class	2D Diagram	3D Interactions
PRD_900017	D, E	triacetyl-beta-chitotriose	Oligosaccharide /  Inhibitor		--

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.15 Å
• R-Value Free: 0.218 
• R-Value Work: 0.173 
• R-Value Observed: 0.175 
• Space Group: P 6₄ 2 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 142.34	α = 90
b = 142.34	β = 90
c = 237.446	γ = 120

Software Package:

Software Name	Purpose
REFMAC	refinement

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2013-05-24 
• Released Date: 2013-07-31 
Deposition Author(s): Yang, Y., Liu, C., Lin, Y.Y., Li, F.

Revision History  

• Version 1.0: 2013-07-31
  Type: Initial release
  
• Version 1.1: 2013-09-04
  Changes: Database references
• Version 1.2: 2013-10-09
  Changes: Database references
• Version 2.0: 2020-07-29
  Type: Remediation
  Reason: Carbohydrate remediation
  Changes: Atomic model, Data collection, Database references, Derived calculations, Structure summary