4Z7P

X-ray structure of racemic ShK Q16K toxin


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.2 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.204 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Pharmaceutical Optimization of Peptide Toxins for Ion Channel Targets: Potent, Selective, and Long-Lived Antagonists of Kv1.3.

Murray, J.K.Qian, Y.X.Liu, B.Elliott, R.Aral, J.Park, C.Zhang, X.Stenkilsson, M.Salyers, K.Rose, M.Li, H.Yu, S.Andrews, K.L.Colombero, A.Werner, J.Gaida, K.Sickmier, E.A.Miu, P.Itano, A.McGivern, J.Gegg, C.V.Sullivan, J.K.Miranda, L.P.

(2015) J.Med.Chem. 58: 6784-6802

  • DOI: 10.1021/acs.jmedchem.5b00495

  • PubMed Abstract: 
  • To realize the medicinal potential of peptide toxins, naturally occurring disulfide-rich peptides, as ion channel antagonists, more efficient pharmaceutical optimization technologies must be developed. Here, we show that the therapeutic properties of ...

    To realize the medicinal potential of peptide toxins, naturally occurring disulfide-rich peptides, as ion channel antagonists, more efficient pharmaceutical optimization technologies must be developed. Here, we show that the therapeutic properties of multiple cysteine toxin peptides can be rapidly and substantially improved by combining direct chemical strategies with high-throughput electrophysiology. We applied whole-molecule, brute-force, structure-activity analoging to ShK, a peptide toxin from the sea anemone Stichodactyla helianthus that inhibits the voltage-gated potassium ion channel Kv1.3, to effectively discover critical structural changes for 15× selectivity against the closely related neuronal ion channel Kv1.1. Subsequent site-specific polymer conjugation resulted in an exquisitely selective Kv1.3 antagonist (>1000× over Kv1.1) with picomolar functional activity in whole blood and a pharmacokinetic profile suitable for weekly administration in primates. The pharmacological potential of the optimized toxin peptide was demonstrated by potent and sustained inhibition of cytokine secretion from T cells, a therapeutic target for autoimmune diseases, in cynomolgus monkeys.


    Organizational Affiliation

    Therapeutic Discovery, Amgen Inc. , 360 Binney Street, Cambridge, Massachusetts 02142, United States.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Potassium channel toxin kappa-stichotoxin-She1a
A
35Stichodactyla helianthusMutation(s): 1 
Find proteins for P29187 (Stichodactyla helianthus)
Go to UniProtKB:  P29187
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download SDF File 
Download CCD File 
A
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.2 Å
  • R-Value Free: 0.227 
  • R-Value Work: 0.204 
  • Space Group: H -3
Unit Cell:
Length (Å)Angle (°)
a = 60.783α = 90.00
b = 60.783β = 90.00
c = 43.592γ = 120.00
Software Package:
Software NamePurpose
REFMACrefinement
SCALEPACKdata scaling
PDB_EXTRACTdata extraction
PHASERphasing
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2015-04-07 
  • Released Date: 2015-09-09 
  • Deposition Author(s): Sickmier, E.A.

Revision History 

  • Version 1.0: 2015-09-09
    Type: Initial release
  • Version 1.1: 2015-09-23
    Type: Database references