4EME

X-ray crystal structure and specificity of the Plasmodium falciparum malaria aminopeptidase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.196 
  • R-Value Work: 0.159 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

X-ray crystal structure and specificity of the Plasmodium falciparum malaria aminopeptidase PfM18AAP.

Sivaraman, K.K.Oellig, C.A.Huynh, K.Atkinson, S.C.Poreba, M.Perugini, M.A.Trenholme, K.R.Gardiner, D.L.Salvesen, G.Drag, M.Dalton, J.P.Whisstock, J.C.McGowan, S.

(2012) J.Mol.Biol. 422: 495-507

  • DOI: 10.1016/j.jmb.2012.06.006

  • PubMed Abstract: 
  • The malarial aminopeptidases have emerged as promising new drug targets for the development of novel antimalarial drugs. The M18AAP of Plasmodium falciparum malaria is a metallo-aminopeptidase that we show demonstrates a highly restricted specificity ...

    The malarial aminopeptidases have emerged as promising new drug targets for the development of novel antimalarial drugs. The M18AAP of Plasmodium falciparum malaria is a metallo-aminopeptidase that we show demonstrates a highly restricted specificity for peptides with an N-terminal Glu or Asp residue. Thus, the enzyme may function alongside other aminopeptidases in effecting the complete degradation or turnover of proteins, such as host hemoglobin, which provides a free amino acid pool for the growing parasite. Inhibition of PfM18AAP's function using antisense RNA is detrimental to the intra-erythrocytic malaria parasite and, hence, it has been proposed as a potential novel drug target. We report the X-ray crystal structure of the PfM18AAP aminopeptidase and reveal its complex dodecameric assembly arranged via dimer and trimer units that interact to form a large tetrahedron shape that completely encloses the 12 active sites within a central cavity. The four entry points to the catalytic lumen are each guarded by 12 large flexible loops that could control substrate entry into the catalytic sites. PfM18AAP thus resembles a proteasomal-like machine with multiple active sites able to degrade peptide substrates that enter the central lumen. The Plasmodium enzyme shows significant structural differences around the active site when compared to recently determined structures of its mammalian and human homologs, which provides a platform from which a rational approach to inhibitor design of new malaria-specific drugs can begin.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biology, Monash University, Clayton Campus, Melbourne, VIC 3800, Australia.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
M18 aspartyl aminopeptidase
A, B, C, D
571Plasmodium falciparumMutation(s): 0 
EC: 3.4.11.21
Find proteins for Q8I2J3 (Plasmodium falciparum)
Go to UniProtKB:  Q8I2J3
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download SDF File 
Download CCD File 
A, B, C, D
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

Unit Cell:
Length (Å)Angle (°)
a = 200.384α = 90.00
b = 200.384β = 90.00
c = 200.384γ = 90.00
Software Package:
Software NamePurpose
PHASERphasing
MOSFLMdata reduction
SCALAdata scaling
BUSTERrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2012-04-11 
  • Released Date: 2012-06-27 
  • Deposition Author(s): McGowan, S.

Revision History 

  • Version 1.0: 2012-06-27
    Type: Initial release
  • Version 1.1: 2013-01-02
    Type: Database references