3EP5

Human AdoMetDC E178Q mutant with no putrescine bound


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.99 Å
  • R-Value Free: 0.246 
  • R-Value Work: 0.214 
  • R-Value Observed: 0.214 

Starting Model: experimental
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wwPDB Validation   3D Report Full Report


This is version 2.0 of the entry. See complete history


Literature

Structural Basis for Putrescine Activation of Human S-Adenosylmethionine Decarboxylase.

Bale, S.Lopez, M.M.Makhatadze, G.I.Fang, Q.Pegg, A.E.Ealick, S.E.

(2008) Biochemistry 47: 13404-13417

  • DOI: https://doi.org/10.1021/bi801732m
  • Primary Citation of Related Structures:  
    3EP3, 3EP4, 3EP5, 3EP6, 3EP7, 3EP8, 3EP9, 3EPA, 3EPB

  • PubMed Abstract: 

    Putrescine (1,4-diaminobutane) activates the autoprocessing and decarboxylation reactions of human S-adenosylmethionine decarboxylase (AdoMetDC), a critical enzyme in the polyamine biosynthetic pathway. In human AdoMetDC, putrescine binds in a buried pocket containing acidic residues Asp174, Glu178, and Glu256. The pocket is away from the active site but near the dimer interface; however, a series of hydrophilic residues connect the putrescine binding site and the active site. Mutation of these acidic residues modulates the effects of putrescine. D174N, E178Q, and E256Q mutants were expressed and dialyzed to remove putrescine and studied biochemically using X-ray crystallography, UV-CD spectroscopy, analytical ultracentrifugation, and ITC binding studies. The results show that the binding of putrescine to the wild type dimeric protein is cooperative. The D174N mutant does not bind putrescine, and the E178Q and E256Q mutants bind putrescine weakly with no cooperativity. The crystal structure of the mutants with and without putrescine and their complexes with S-adenosylmethionine methyl ester were obtained. Binding of putrescine results in a reorganization of four aromatic residues (Phe285, Phe315, Tyr318, and Phe320) and a conformational change in the loop 312-320. The loop shields putrescine from the external solvent, enhancing its electrostatic and hydrogen bonding effects. The E256Q mutant with putrescine added shows an alternate conformation of His243, Glu11, Lys80, and Ser229, the residues that link the active site and the putrescine binding site, suggesting that putrescine activates the enzyme through electrostatic effects and acts as a switch to correctly orient key catalytic residues.


  • Organizational Affiliation

    Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
S-adenosylmethionine decarboxylase beta chainA [auth B]67Homo sapiensMutation(s): 0 
Gene Names: AMD1AMD
EC: 4.1.1.50
UniProt & NIH Common Fund Data Resources
Find proteins for P17707 (Homo sapiens)
Explore P17707 
Go to UniProtKB:  P17707
PHAROS:  P17707
GTEx:  ENSG00000123505 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP17707
Sequence Annotations
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
S-adenosylmethionine decarboxylase alpha chainB [auth A]260Homo sapiensMutation(s): 1 
Gene Names: AMD1AMD
EC: 4.1.1.50
UniProt & NIH Common Fund Data Resources
Find proteins for P17707 (Homo sapiens)
Explore P17707 
Go to UniProtKB:  P17707
PHAROS:  P17707
GTEx:  ENSG00000123505 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP17707
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.99 Å
  • R-Value Free: 0.246 
  • R-Value Work: 0.214 
  • R-Value Observed: 0.214 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 90.569α = 90
b = 56.255β = 109.73
c = 74.05γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
CNSrefinement
PDB_EXTRACTdata extraction
ADSCdata collection
HKL-2000data reduction
HKL-2000data scaling
CNSphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2008-12-23
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2017-10-25
    Changes: Refinement description
  • Version 1.3: 2021-10-20
    Changes: Database references, Derived calculations
  • Version 1.4: 2023-09-06
    Changes: Data collection, Refinement description
  • Version 2.0: 2023-11-15
    Changes: Atomic model, Data collection, Derived calculations