3EQB

X-ray structure of the human mitogen-activated protein kinase kinase 1 (MEK1) in a complex with ligand and MgATP

• PDB DOI: https://doi.org/10.2210/pdb3EQB/pdb

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


• Deposited: 2008-09-30 Released: 2008-11-11 
• Deposition Author(s): Ohren, J.F., Pavlovsky, A., Zhang, E.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.62 Å
• R-Value Free: 0.264 
• R-Value Work: 0.210 
• R-Value Observed: 0.212 

Starting Model: experimental

Literature

2-Alkylamino- and alkoxy-substituted 2-amino-1,3,4-oxadiazoles-O-Alkyl benzohydroxamate esters replacements retain the desired inhibition and selectivity against MEK (MAP ERK kinase).

Warmus, J.S., Flamme, C., Zhang, L.Y., Barrett, S., Bridges, A., Chen, H., Gowan, R., Kaufman, M., Sebolt-Leopold, J., Leopold, W., Merriman, R., Ohren, J., Pavlovsky, A., Przybranowski, S., Tecle, H., Valik, H., Whitehead, C., Zhang, E.

(2008) Bioorg Med Chem Lett 18: 6171-6174

• PubMed: 18951019 
• DOI: https://doi.org/10.1016/j.bmcl.2008.10.015
• Primary Citation of Related Structures:  
  3EQB


• PubMed Abstract: 
  

  This paper reports a second generation MEK inhibitor. The previously reported potent and efficacious MEK inhibitor, PD-184352 (CI-1040), contains an integral hydroxamate moiety. This compound suffered from less than ideal solubility and metabolic stability. An oxadiazole moiety behaves as a bioisostere for the hydroxamate group, leading to a more metabolically stable and efficacious MEK inhibitor.

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Organizational Affiliation: 

Department of Chemistry, Pfizer Global Research and Development, Ann Arbor, MI 48105, USA. [e-mail]

Biological Assembly 1  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Homo 2-mer - A2 

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

Macromolecule Content

• Total Structure Weight: 37.87 kDa 
• Atom Count: 2,347 
• Modelled Residue Count: 289 
• Deposited Residue Count: 333 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Dual specificity mitogen-activated protein kinase kinase 1	A	333	Homo sapiens	Mutation(s): 0  Gene Names: MAP2K1, MEK1, PRKMK1 EC: 2.7.12.2
UniProt & NIH Common Fund Data Resources
Find proteins for Q02750 (Homo sapiens) Explore Q02750  Go to UniProtKB:  Q02750
PHAROS:  Q02750 GTEx:  ENSG00000169032

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
ATP	B [auth A]	ADENOSINE-5'-TRIPHOSPHATE C10 H16 N5 O13 P3 ZKHQWZAMYRWXGA-KQYNXXCUSA-N
LUG	D [auth A]	N-(5-{3,4-difluoro-2-[(2-fluoro-4-iodophenyl)amino]phenyl}-1,3,4-oxadiazol-2-yl)ethane-1,2-diamine C16 H13 F3 I N5 O FPDWDLAITHFTTP-UHFFFAOYSA-N
MG	C [auth A]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
LUG	PDBBind:  3EQB	IC50: 1.50e+7 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.62 Å
• R-Value Free: 0.264 
• R-Value Work: 0.210 
• R-Value Observed: 0.212 
• Space Group: P 6₂

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 82.128	α = 90
b = 82.128	β = 90
c = 129.099	γ = 120

Software Package:

Software Name	Purpose
HKL-2000	data collection
REFMAC	refinement
DENZO	data reduction
SCALEPACK	data scaling
REFMAC	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2008-11-11 
Deposition Author(s): Ohren, J.F., Pavlovsky, A., Zhang, E.

Revision History  

• Version 1.0: 2008-11-11
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Version format compliance
• Version 1.2: 2023-09-06
  Changes: Data collection, Database references, Derived calculations, Refinement description