6Q2A

Trypanosoma brucei CLK1 kinase domain in complex with a covalent aminobenzimidazole inhibitor AB1


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.60 Å
  • R-Value Free: 0.313 
  • R-Value Work: 0.266 
  • R-Value Observed: 0.268 

wwPDB Validation   3D Report Full Report


Ligand Structure Quality Assessment 


This is version 1.3 of the entry. See complete history


Literature

Targeting the trypanosome kinetochore with CLK1 protein kinase inhibitors.

Saldivia, M.Fang, E.Ma, X.Myburgh, E.Carnielli, J.B.T.Bower-Lepts, C.Brown, E.Ritchie, R.Lakshminarayana, S.B.Chen, Y.L.Patra, D.Ornelas, E.Koh, H.X.Y.Williams, S.L.Supek, F.Paape, D.McCulloch, R.Kaiser, M.Barrett, M.P.Jiricek, J.Diagana, T.T.Mottram, J.C.Rao, S.P.S.

(2020) Nat Microbiol 5: 1207-1216

  • DOI: https://doi.org/10.1038/s41564-020-0745-6
  • Primary Citation of Related Structures:  
    6Q2A

  • PubMed Abstract: 

    The kinetochore is a macromolecular structure that assembles on the centromeres of chromosomes and provides the major attachment point for spindle microtubules during mitosis. In Trypanosoma brucei, the proteins that make up the kinetochore are highly divergent; the inner kinetochore comprises at least 20 distinct and essential proteins (KKT1-20) that include four protein kinases-CLK1 (also known as KKT10), CLK2 (also known as KKT19), KKT2 and KKT3. Here, we report the identification and characterization of the amidobenzimidazoles (AB) protein kinase inhibitors that show nanomolar potency against T. brucei bloodstream forms, Leishmania and Trypanosoma cruzi. We performed target deconvolution analysis using a selection of 29 T. brucei mutants that overexpress known essential protein kinases, and identified CLK1 as a primary target. Biochemical studies and the co-crystal structure of CLK1 in complex with AB1 show that the irreversible competitive inhibition of CLK1 is dependent on a Michael acceptor forming an irreversible bond with Cys 215 in the ATP-binding pocket, a residue that is not present in human CLK1, thereby providing selectivity. Chemical inhibition of CLK1 impairs inner kinetochore recruitment and compromises cell-cycle progression, leading to cell death. This research highlights a unique drug target for trypanosomatid parasitic protozoa and a new chemical tool for investigating the function of their divergent kinetochores.


  • Organizational Affiliation

    York Biomedical Research Institute and Department of Biology, University of York, York, UK.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Protein kinase, putative
A, B, C, D, E
A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P
354Trypanosoma brucei brucei TREU927Mutation(s): 0 
Gene Names: Tb11.01.4230
EC: 2.7.1
UniProt
Find proteins for Q382U0 (Trypanosoma brucei brucei (strain 927/4 GUTat10.1))
Explore Q382U0 
Go to UniProtKB:  Q382U0
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ382U0
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
5XH (Subject of Investigation/LOI)
Query on 5XH

Download Ideal Coordinates CCD File 
BA [auth D]
CB [auth L]
EB [auth M]
FA [auth E]
GB [auth N]
BA [auth D],
CB [auth L],
EB [auth M],
FA [auth E],
GB [auth N],
JA [auth F],
JB [auth O],
LA [auth G],
MB [auth P],
OA [auth H],
R [auth A],
SA [auth I],
V [auth B],
WA [auth J],
Z [auth C],
ZA [auth K]
~{N}-[1-[(3~{R})-1-[4-(dimethylamino)but-2-enoyl]azepan-3-yl]-7-methyl-benzimidazol-2-yl]-2-methyl-pyridine-4-carboxamide
C27 H34 N6 O2
SKLAQDNYYXAFGK-QWDXWUACSA-N
SO4
Query on SO4

Download Ideal Coordinates CCD File 
AA [auth D]
AB [auth L]
BB [auth L]
CA [auth E]
DA [auth E]
AA [auth D],
AB [auth L],
BB [auth L],
CA [auth E],
DA [auth E],
DB [auth M],
EA [auth E],
FB [auth N],
GA [auth F],
HA [auth F],
HB [auth O],
IA [auth F],
IB [auth O],
KA [auth G],
KB [auth P],
LB [auth P],
MA [auth H],
NA [auth H],
PA [auth I],
Q [auth A],
QA [auth I],
RA [auth I],
S [auth B],
T [auth B],
TA [auth J],
U [auth B],
UA [auth J],
VA [auth J],
W [auth C],
X [auth C],
XA [auth K],
Y [auth C],
YA [auth K]
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.60 Å
  • R-Value Free: 0.313 
  • R-Value Work: 0.266 
  • R-Value Observed: 0.268 
  • Space Group: P 31
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 147.15α = 90
b = 147.15β = 90
c = 264.8γ = 120
Software Package:
Software NamePurpose
Aimlessdata scaling
PHENIXrefinement
PDB_EXTRACTdata extraction
xia2data reduction
PHASERphasing

Structure Validation

View Full Validation Report



Ligand Structure Quality Assessment 


Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2020-06-17
    Type: Initial release
  • Version 1.1: 2020-07-29
    Changes: Database references
  • Version 1.2: 2020-10-07
    Changes: Database references
  • Version 1.3: 2023-10-11
    Changes: Data collection, Database references, Refinement description