5EGP

Crystal structure of the S-methyltransferase TmtA


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.5 Å
  • R-Value Free: 0.164 
  • R-Value Work: 0.132 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Sequential Inactivation of Gliotoxin by the S-Methyltransferase TmtA.

Duell, E.R.Glaser, M.Le Chapelain, C.Antes, I.Groll, M.Huber, E.M.

(2016) Acs Chem.Biol. 11: 1082-1089

  • DOI: 10.1021/acschembio.5b00905

  • PubMed Abstract: 
  • The epipolythiodioxopiperazine (ETP) gliotoxin mediates toxicity via its reactive thiol groups and thereby contributes to virulence of the human pathogenic fungus Aspergillus fumigatus. Self-intoxication of the mold is prevented either by reversible ...

    The epipolythiodioxopiperazine (ETP) gliotoxin mediates toxicity via its reactive thiol groups and thereby contributes to virulence of the human pathogenic fungus Aspergillus fumigatus. Self-intoxication of the mold is prevented either by reversible oxidation of reduced gliotoxin or by irreversible conversion to bis(methylthio)gliotoxin. The latter is produced by the S-methyltransferase TmtA and attenuates ETP biosynthesis. Here, we report the crystal structure of TmtA in complex with S-(5'-adenosyl)-l-homocysteine. TmtA features one substrate and one cofactor binding pocket per protein, and thus, bis-thiomethylation of gliotoxin occurs sequentially. Molecular docking of substrates and products into the active site of TmtA reveals that gliotoxin forms specific interactions with the protein surroundings, and free energy calculations indicate that methylation of the C10a-SH group precedes alkylation of the C3-SH site. Altogether, TmtA is well suited to selectively convert gliotoxin and to control its biosynthesis, suggesting that homologous enzymes serve to regulate the production of their toxic natural sulfur compounds in a similar manner.


    Organizational Affiliation

    Center for Integrated Protein Science Munich (CIPSM) at the Department Chemie, Technische Universit√§t M√ľnchen , Lichtenbergstr. 4, 85748 Garching, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
UbiE/COQ5 family methyltransferase, putative
A, B
314Aspergillus fumigatus Z5Mutation(s): 0 
Find proteins for A0A0J5Q3C4 (Aspergillus fumigatus Z5)
Go to UniProtKB:  A0A0J5Q3C4
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download SDF File 
Download CCD File 
A, B
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
ACT
Query on ACT

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Download CCD File 
A, B
ACETATE ION
C2 H3 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-M
 Ligand Interaction
SAH
Query on SAH

Download SDF File 
Download CCD File 
A, B
S-ADENOSYL-L-HOMOCYSTEINE
C14 H20 N6 O5 S
ZJUKTBDSGOFHSH-WFMPWKQPSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.5 Å
  • R-Value Free: 0.164 
  • R-Value Work: 0.132 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 49.100α = 90.00
b = 109.210β = 112.44
c = 59.940γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
SHARPphasing
XSCALEdata scaling
XDSdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
DFGGermanySFB749
Hans-Fischer-GesellschaftGermany--

Revision History 

  • Version 1.0: 2016-02-03
    Type: Initial release
  • Version 1.1: 2016-04-27
    Type: Database references