Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

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

Macromolecule Content

• Total Structure Weight: 33.50 kDa 
• Atom Count: 2007 
• Modelled Residue Count: 249 
• Deposited Residue Count: 285 
• Unique protein chains: 1

2X6E

Aurora-A bound to an inhibitor

• DOI: 10.2210/pdb2X6E/pdb

• Classification: TRANSFERASE
• Organism(s): Homo sapiens
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2010-02-17 Released: 2010-07-07 
• Deposition Author(s): Kosmopoulou, M., Bayliss, R.

---

Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.35 Å
• R-Value Free: 0.299 
• R-Value Work: 0.227 
• R-Value Observed: 0.231 

Literature

Imidazo[4,5-b]pyridine derivatives as inhibitors of Aurora kinases: lead optimization studies toward the identification of an orally bioavailable preclinical development candidate.

Bavetsias, V., Large, J.M., Sun, C., Bouloc, N., Kosmopoulou, M., Matteucci, M., Wilsher, N.E., Martins, V., Reynisson, J., Atrash, B., Faisal, A., Urban, F., Valenti, M., de Haven Brandon, A., Box, G., Raynaud, F.I., Workman, P., Eccles, S.A., Bayliss, R., Blagg, J., Linardopoulos, S., McDonald, E.

(2010) J Med Chem 53: 5213-5228

• PubMed: 20565112 
• DOI: 10.1021/jm100262j
• Primary Citation of Related Structures:  
  2X6D, 2X6E


• PubMed Abstract: 
  

Lead optimization studies using 7 as the starting point led to a new class of imidazo[4,5-b]pyridine-based inhibitors of Aurora kinases that possessed the 1-benzylpiperazinyl motif at the 7-position, and displayed favorable in vitro properties. Cocrystallization of Aurora-A with 40c (CCT137444) provided a clear understanding into the interactions of this novel class of inhibitors with the Aurora kinases. Subsequent physicochemical property refinement by the incorporation of solubilizing groups led to the identification of 3-((4-(6-bromo-2-(4-(4-methylpiperazin-1-yl)phenyl)-3H-imidazo[4,5-b]pyridin-7-yl)piperazin-1-yl)methyl)-5-methylisoxazole (51, CCT137690) which is a potent inhibitor of Aurora kinases (Aurora-A IC(50) = 0.015 +/- 0.003 muM, Aurora-B IC(50) = 0.025 muM, Aurora-C IC(50) = 0.019 muM). Compound 51 is highly orally bioavailable, and in in vivo efficacy studies it inhibited the growth of SW620 colon carcinoma xenografts following oral administration with no observed toxicities as defined by body weight loss.

---

Organizational Affiliation: 

Cancer Research UK Centre for Cancer Therapeutics, The Institute of Cancer Research, 15 Cotswold Road, Sutton, Surrey, SM2 5NG, United Kingdom. [e-mail]

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
SERINE/THREONINE-PROTEIN KINASE 6	A	285	Homo sapiens	Mutation(s): 0  Gene Names: AURKA, AIK, AIRK1, ARK1, AURA, AYK1, BTAK, IAK1, STK15, STK6 EC: 2.7.11.1
Find proteins for O14965 (Homo sapiens) Explore O14965  Go to UniProtKB:  O14965
NIH Common Fund Data Resources
PHAROS:  O14965 GTEx:  ENSG00000087586

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
YM4	B [auth A]	6-BROMO-7-{4-[(5-METHYLISOXAZOL-3-YL)METHYL]PIPERAZIN-1-YL}-2-[4-(4-METHYLPIPERAZIN-1-YL)PHENYL]-1H-IMIDAZO[4,5-B]PYRIDINE C26 H31 Br N8 O GFLQCBTXTRCREJ-UHFFFAOYSA-N

External Ligand Annotations
ID	Binding Affinity (Sequence Identity %)
YM4	IC50:  15   nM  BindingDB
YM4	IC50 :  15   nM  PDBBind

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.35 Å
• R-Value Free: 0.299 
• R-Value Work: 0.227 
• R-Value Observed: 0.231 
• Space Group: P 6₁ 2 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 83.25	α = 90
b = 83.25	β = 90
c = 163.31	γ = 120

Software Package:

Software Name	Purpose
PHENIX	refinement
MOSFLM	data reduction
SCALA	data scaling
PHASER	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2010-02-17 
• Released Date: 2010-07-07 
Deposition Author(s): Kosmopoulou, M., Bayliss, R.

Revision History  

• Version 1.0: 2010-07-07
  Type: Initial release
  
• Version 1.1: 2011-05-08
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2018-02-28
  Changes: Database references