4NMX

PCSK9(deltaCRD) in complex with phage-derived inhibitory peptide 2-8


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.85 Å
  • R-Value Free: 0.222 
  • R-Value Work: 0.185 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Identification of a Small Peptide That Inhibits PCSK9 Protein Binding to the Low Density Lipoprotein Receptor.

Zhang, Y.Eigenbrot, C.Zhou, L.Shia, S.Li, W.Quan, C.Tom, J.Moran, P.Di Lello, P.Skelton, N.J.Kong-Beltran, M.Peterson, A.Kirchhofer, D.

(2014) J.Biol.Chem. 289: 942-955

  • DOI: 10.1074/jbc.M113.514067

  • PubMed Abstract: 
  • PCSK9 (proprotein convertase subtilisin/kexin type 9) is a negative regulator of the hepatic LDL receptor, and clinical studies with PCSK9-inhibiting antibodies have demonstrated strong LDL-c-lowering effects. Here we screened phage-displayed peptide ...

    PCSK9 (proprotein convertase subtilisin/kexin type 9) is a negative regulator of the hepatic LDL receptor, and clinical studies with PCSK9-inhibiting antibodies have demonstrated strong LDL-c-lowering effects. Here we screened phage-displayed peptide libraries and identified the 13-amino acid linear peptide Pep2-8 as the smallest PCSK9 inhibitor with a clearly defined mechanism of inhibition that has been described. Pep2-8 bound to PCSK9 with a KD of 0.7 μm but did not bind to other proprotein convertases. It fully restored LDL receptor surface levels and LDL particle uptake in PCSK9-treated HepG2 cells. The crystal structure of Pep2-8 bound to C-terminally truncated PCSK9 at 1.85 Å resolution showed that the peptide adopted a strand-turn-helix conformation, which is remarkably similar to its solution structure determined by NMR. Consistent with the functional binding site identified by an Ala scan of PCSK9, the structural Pep2-8 contact region of about 400 Å(2) largely overlapped with that contacted by the EGF(A) domain of the LDL receptor, suggesting a competitive inhibition mechanism. Consistent with this, Pep2-8 inhibited LDL receptor and EGF(A) domain binding to PCSK9 with IC50 values of 0.8 and 0.4 μm, respectively. Remarkably, Pep2-8 mimicked secondary structural elements of the EGF(A) domain that interact with PCSK9, notably the β-strand and a discontinuous short α-helix, and it engaged in the same β-sheet hydrogen bonds as EGF(A) does. Although Pep2-8 itself may not be amenable to therapeutic applications, this study demonstrates the feasibility of developing peptidic inhibitors to functionally relevant sites on PCSK9.


    Organizational Affiliation

    From the Departments of Early Discovery Biochemistry.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Proprotein convertase subtilisin/kexin type 9
A
125Homo sapiensMutation(s): 0 
Gene Names: PCSK9 (NARC1)
EC: 3.4.21.-
Find proteins for Q8NBP7 (Homo sapiens)
Go to Gene View: PCSK9
Go to UniProtKB:  Q8NBP7
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Proprotein convertase subtilisin/kexin type 9
B
308Homo sapiensMutation(s): 0 
Gene Names: PCSK9 (NARC1)
EC: 3.4.21.-
Find proteins for Q8NBP7 (Homo sapiens)
Go to Gene View: PCSK9
Go to UniProtKB:  Q8NBP7
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
peptide 2-8
Z
15N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Small Molecules
Modified Residues  2 Unique
IDChainsTypeFormula2D DiagramParent
NH2
Query on NH2
Z
NON-POLYMERH2 N

--

ACE
Query on ACE
Z
NON-POLYMERC2 H4 O

--

Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.85 Å
  • R-Value Free: 0.222 
  • R-Value Work: 0.185 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 95.102α = 90.00
b = 70.765β = 96.08
c = 70.413γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
PHASERphasing
HKL-2000data reduction
Blu-Icedata collection
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-12-04
    Type: Initial release
  • Version 1.1: 2014-01-29
    Type: Database references