6N47

The structure of SB-2-204-tubulin complex


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.60 Å
  • R-Value Free: 0.246 
  • R-Value Work: 0.201 
  • R-Value Observed: 0.203 

wwPDB Validation   3D Report Full Report


Ligand Structure Quality Assessment 


This is version 1.3 of the entry. See complete history


Literature

X-ray Crystal Structure Guided Discovery and Antitumor Efficacy of Dihydroquinoxalinone as Potent Tubulin Polymerization Inhibitors.

Arnst, K.E.Banerjee, S.Wang, Y.Chen, H.Li, Y.Yang, L.Li, W.Miller, D.D.Li, W.

(2019) ACS Chem Biol 14: 2810-2821

  • DOI: https://doi.org/10.1021/acschembio.9b00696
  • Primary Citation of Related Structures:  
    6N47

  • PubMed Abstract: 

    Because of its multifaceted role in cellular functions, tubulin is a validated and productive drug target for cancer therapy. While many tubulin inhibitors demonstrate clinical efficacy, they are often limited by the development of multidrug resistance. Therefore, implementation of tubulin inhibitors that can overcome resistance could provide significant therapeutic benefits. To optimize our previously reported tubulin inhibitor, 4a , we designed and synthesized two new analogues, SB202 and SB204 , based on the crystal structure of 4a in complex with tubulin protein. SB202 and SB204 achieved enhanced binding at the colchicine site in tubulin and also showed improved metabolic stability and antiproliferative potency in vitro . Functional studies confirmed that SB202 and SB204 inhibit tubulin polymerization, arrest cells in the G 2 /M phase of the cell cycle, interfere with cancer cell migration and proliferation, and enhance apoptotic cascades. When evaluated in vivo , SB202 exhibited antitumor and vascular disrupting action against paclitaxel-resistant mouse xenograft models, strongly suggesting the potential of this scaffold to overcome multidrug resistance for cancer therapy.


  • Organizational Affiliation

    Department of Pharmaceutical Sciences, College of Pharmacy , University of Tennessee Health Science Center , Memphis , Tennessee 38163 , United States.


Macromolecules
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Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Tubulin alpha-1B chain
A, C
450Sus scrofaMutation(s): 0 
Gene Names: TUBA1B
EC: 3.6.5
UniProt
Find proteins for Q2XVP4 (Sus scrofa)
Explore Q2XVP4 
Go to UniProtKB:  Q2XVP4
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ2XVP4
Sequence Annotations
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  • Reference Sequence
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Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Tubulin beta-2B chain
B, D
445Bos taurusMutation(s): 0 
Gene Names: TUBB2B
UniProt
Find proteins for Q6B856 (Bos taurus)
Explore Q6B856 
Go to UniProtKB:  Q6B856
Entity Groups  
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UniProt GroupQ6B856
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  • Reference Sequence
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Entity ID: 3
MoleculeChains Sequence LengthOrganismDetailsImage
Stathmin-4143Rattus norvegicusMutation(s): 0 
Gene Names: Stmn4
UniProt
Find proteins for P63043 (Rattus norvegicus)
Explore P63043 
Go to UniProtKB:  P63043
Entity Groups  
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UniProt GroupP63043
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  • Reference Sequence
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Entity ID: 4
MoleculeChains Sequence LengthOrganismDetailsImage
Uncharacterized protein384Gallus gallusMutation(s): 0 
Gene Names: TTL
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
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  • Reference Sequence
Small Molecules
Ligands 8 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
GTP
Query on GTP

Download Ideal Coordinates CCD File 
G [auth A],
Q [auth C],
T [auth D]
GUANOSINE-5'-TRIPHOSPHATE
C10 H16 N5 O14 P3
XKMLYUALXHKNFT-UUOKFMHZSA-N
ACP
Query on ACP

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X [auth F]PHOSPHOMETHYLPHOSPHONIC ACID ADENYLATE ESTER
C11 H18 N5 O12 P3
UFZTZBNSLXELAL-IOSLPCCCSA-N
GDP
Query on GDP

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K [auth B]GUANOSINE-5'-DIPHOSPHATE
C10 H15 N5 O11 P2
QGWNDRXFNXRZMB-UUOKFMHZSA-N
KB4
Query on KB4

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P [auth B],
V [auth D]
4-(2-chloropyrido[3,2-d]pyrimidin-4-yl)-7-methoxy-3,4-dihydroquinoxalin-2(1H)-one
C16 H12 Cl N5 O2
LHARPASIDWIFEJ-UHFFFAOYSA-N
MES
Query on MES

Download Ideal Coordinates CCD File 
N [auth B],
O [auth B]
2-(N-MORPHOLINO)-ETHANESULFONIC ACID
C6 H13 N O4 S
SXGZJKUKBWWHRA-UHFFFAOYSA-N
CA
Query on CA

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H [auth A],
M [auth B],
S [auth C],
W [auth E]
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
CL
Query on CL

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I [auth A]CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
MG
Query on MG

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J [auth A],
L [auth B],
R [auth C],
U [auth D]
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.60 Å
  • R-Value Free: 0.246 
  • R-Value Work: 0.201 
  • R-Value Observed: 0.203 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 105.295α = 90
b = 157.835β = 90
c = 182.068γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
HKL-2000data reduction
HKL-2000data scaling
MOLREPphasing

Structure Validation

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Ligand Structure Quality Assessment 


Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2019-11-13
    Type: Initial release
  • Version 1.1: 2019-11-27
    Changes: Database references
  • Version 1.2: 2020-01-01
    Changes: Database references
  • Version 1.3: 2024-03-13
    Changes: Data collection, Database references, Derived calculations