4MLT

Structure of a monodentate 3-hydroxy-4H-pyran-4-thione ligand bound to hCAII


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.241 
  • R-Value Work: 0.172 
  • R-Value Observed: 0.176 

wwPDB Validation   3D Report Full Report


This is version 1.0 of the entry. See complete history


Literature

'Unconventional' coordination chemistry by metal chelating fragments in a metalloprotein active site.

Martin, D.P.Blachly, P.G.Marts, A.R.Woodruff, T.M.de Oliveira, C.A.McCammon, J.A.Tierney, D.L.Cohen, S.M.

(2014) J Am Chem Soc 136: 5400-5406

  • DOI: 10.1021/ja500616m
  • Primary Citation of Related Structures:  
    4MLT, 4MLX

  • PubMed Abstract: 
  • The binding of three closely related chelators: 5-hydroxy-2-methyl-4H-pyran-4-thione (allothiomaltol, ATM), 3-hydroxy-2-methyl-4H-pyran-4-thione (thiomaltol, TM), and 3-hydroxy-4H-pyran-4-thione (thiopyromeconic acid, TPMA) to the active site of human carbonic anhydrase II (hCAII) has been investigated ...

    The binding of three closely related chelators: 5-hydroxy-2-methyl-4H-pyran-4-thione (allothiomaltol, ATM), 3-hydroxy-2-methyl-4H-pyran-4-thione (thiomaltol, TM), and 3-hydroxy-4H-pyran-4-thione (thiopyromeconic acid, TPMA) to the active site of human carbonic anhydrase II (hCAII) has been investigated. Two of these ligands display a monodentate mode of coordination to the active site Zn(2+) ion in hCAII that is not recapitulated in model complexes of the enzyme active site. This unprecedented binding mode in the hCAII-thiomaltol complex has been characterized by both X-ray crystallography and X-ray spectroscopy. In addition, the steric restrictions of the active site force the ligands into a 'flattened' mode of coordination compared with inorganic model complexes. This change in geometry has been shown by density functional computations to significantly decrease the strength of the metal-ligand binding. Collectively, these data demonstrate that the mode of binding by small metal-binding groups can be significantly influenced by the protein active site. Diminishing the strength of the metal-ligand bond results in unconventional modes of metal coordination not found in typical coordination compounds or even carefully engineered active site models, and understanding these effects is critical to the rational design of inhibitors that target clinically relevant metalloproteins.


    Organizational Affiliation

    Department of Chemistry and Biochemistry, §Pharmacology, and ∥Howard Hughes Medical Institute, University of California, San Diego , La Jolla, California 92093, United States.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Carbonic anhydrase 2A260Homo sapiensMutation(s): 0 
Gene Names: CA2
EC: 4.2.1.1
UniProt & NIH Common Fund Data Resources
Find proteins for P00918 (Homo sapiens)
Explore P00918 
Go to UniProtKB:  P00918
PHAROS:  P00918
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 4 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MBO
Query on MBO

Download Ideal Coordinates CCD File 
C [auth A]MERCURIBENZOIC ACID
C7 H5 Hg O2
FVFZSVRSDNUCGG-UHFFFAOYSA-N
 Ligand Interaction
TM4
Query on TM4

Download Ideal Coordinates CCD File 
D [auth A]3-hydroxy-2-methyl-4H-pyran-4-thione
C6 H6 O2 S
GKLSXUGPECNEMX-UHFFFAOYSA-N
 Ligand Interaction
DMS
Query on DMS

Download Ideal Coordinates CCD File 
E [auth A]DIMETHYL SULFOXIDE
C2 H6 O S
IAZDPXIOMUYVGZ-UHFFFAOYSA-N
 Ligand Interaction
ZN
Query on ZN

Download Ideal Coordinates CCD File 
B [auth A]ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
TM4Ki:  1400000   nM  Binding MOAD
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.241 
  • R-Value Work: 0.172 
  • R-Value Observed: 0.176 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 42.145α = 90
b = 41.472β = 104.19
c = 72.029γ = 90
Software Package:
Software NamePurpose
APEXdata collection
PHASERphasing
REFMACrefinement
APEXdata reduction

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2014-07-02
    Type: Initial release