Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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Protein Workshop | Ligand Explorer

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

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

Macromolecule Content

• Total Structure Weight: 106103.01 
• Atom Count: 7397 
• 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


• 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 

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:  
  4KXD, 4KXC, 4KXB, 4KXA, 4KX9, 4KX8


• 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

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
Glutamyl aminopeptidase	A	888	Homo sapiens	Mutation(s): 0  Gene Names: ENPEP EC: 3.4.11.7
Find proteins for Q07075 (Homo sapiens) Go to Gene View: ENPEP Go to UniProtKB:  Q07075

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram & Interactions
ZN	A	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N
NAG	A	N-ACETYL-D-GLUCOSAMINE C8 H15 N O6 OVRNDRQMDRJTHS-FMDGEEDCSA-N

Experimental Data & Validation

Experimental Data

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

Unit Cell:

Length (Å)	Angle (°)
a = 142.340	α = 90.00
b = 142.340	β = 90.00
c = 237.446	γ = 120.00

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
  Type: Database references
• Version 1.2: 2013-10-09
  Type: Database references