Biological Assembly 1  

 3D View: Structure | Ligand Interaction

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

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

Macromolecule Content

• Total Structure Weight: 37332.62 
• Atom Count: 2217 
• Residue Count: 323 
• Unique protein chains: 1

2R0U

Crystal Structure of Chek1 in Complex with Inhibitor 54

• DOI: 10.2210/pdb2R0U/pdb

• Classification: TRANSFERASE
• Organism(s): Homo sapiens
• Expression System: Spodoptera frugiperda


• Deposited: 2007-08-21 Released: 2007-10-30 
• Deposition Author(s): Yan, Y., Ikuta, M.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.9 Å
• R-Value Free: 0.218 
• R-Value Work: 0.195 

Literature

Synthesis and evaluation of substituted benzoisoquinolinones as potent inhibitors of Chk1 kinase.

Garbaccio, R.M., Huang, S., Tasber, E.S., Fraley, M.E., Yan, Y., Munshi, S., Ikuta, M., Kuo, L., Kreatsoulas, C., Stirdivant, S., Drakas, B., Rickert, K., Walsh, E.S., Hamilton, K.A., Buser, C.A., Hardwick, J., Mao, X., Beck, S.C., Abrams, M.T., Tao, W., Lobell, R., Sepp-Lorenzino, L., Hartman, G.D.

(2007) Bioorg.Med.Chem.Lett. 17: 6280-6285

• PubMed: 17900896 
• DOI: 10.1016/j.bmcl.2007.09.007


• PubMed Abstract: 
  

From HTS lead 1, a novel benzoisoquinolinone class of ATP-competitive Chk1 inhibitors was devised and synthesized via a photochemical route. Using X-ray crystallography as a guide, potency was rapidly enhanced through the installation of a tethered basic amine designed to interact with an acidic residue (Glu91) in the enzyme pocket. Further SAR was explored at the solvent front and near to the H1 pocket and resulted in the discovery of low MW, sub-nanomolar inhibitors of Chk1.

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Organizational Affiliation: 

Department of Medicinal Chemistry, Merck Research Laboratories, West Point, PA 19486, USA. [e-mail]

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
Serine/threonine-protein kinase Chk1	A	323	Homo sapiens	Mutation(s): 0  Gene Names: CHEK1 (CHK1) EC: 2.7.11.1
Find proteins for O14757 (Homo sapiens) Go to Gene View: CHEK1 Go to UniProtKB:  O14757

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram & Interactions
M54	A	6-(3-aminopropyl)-4-(3-hydroxyphenyl)-9-(1H-pyrazol-4-yl)benzo[h]isoquinolin-1(2H)-one C25 H22 N4 O2 BUSJQQYKXHYDNN-UHFFFAOYSA-N

External Ligand Annotations
ID	Binding Affinity (Sequence Identity %)
M54	IC50: 1 nM (100) BINDINGDB
M54	IC50: 1 nM BINDINGMOAD
M54	IC50: 1 nM PDBBIND

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.9 Å
• R-Value Free: 0.218 
• R-Value Work: 0.195 
• Space Group: P 1 2₁ 1

Unit Cell:

Length (Å)	Angle (°)
a = 45.260	α = 90.00
b = 65.540	β = 94.27
c = 58.500	γ = 90.00

Software Package:

Software Name	Purpose
CrystalClear	data collection
d*TREK	data scaling
CNS	phasing
d*TREK	data reduction
BUSTER-TNT	refinement

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2007-08-21 
• Released Date: 2007-10-30 
• Deposition Author(s): Yan, Y., Ikuta, M.

Revision History 

• Version 1.0: 2007-10-30
  Type: Initial release
• Version 1.1: 2011-07-13
  Type: Version format compliance