4C0R

Molecular and structural basis of glutathione import in Gram-positive bacteria via GshT and the cystine ABC importer TcyBC of Streptococcus mutans.


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.547 Å
  • R-Value Free: 0.183 
  • R-Value Work: 0.155 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Molecular and Structural Basis of Glutathione Import in Gram-Positive Bacteria Via Gsht and the Cystine Abc Importer Tcybc of Streptococcus Mutans.

Vergauwen, B.Verstraete, K.Senadheera, D.B.Dansercoer, A.Cvitkovitch, D.G.Guedon, E.Savvides, S.N.

(2013) Mol.Microbiol. 89: 288

  • DOI: 10.1111/mmi.12274

  • PubMed Abstract: 
  • Glutathione (GSH) protects cells against oxidative injury and maintains a range of vital functions across all branches of life. Despite recent advances in our understanding of the transport mechanisms responsible for maintaining the spatiotemporal ho ...

    Glutathione (GSH) protects cells against oxidative injury and maintains a range of vital functions across all branches of life. Despite recent advances in our understanding of the transport mechanisms responsible for maintaining the spatiotemporal homeostasis of GSH and its conjugates in eukaryotes and Gram-negative bacteria, the molecular and structural basis of GSH import into Gram-positive bacteria has remained largely uncharacterized. Here, we employ genetic, biochemical and structural studies to investigate a possible glutathione import axis in Streptococcus mutans, an organism that has hitherto served as a model system. We show that GshT, a type 3 solute binding protein, displays physiologically relevant affinity for GSH and glutathione disulfide (GSSG). The crystal structure of GshT in complex with GSSG reveals a collapsed structure whereby the GS-I-leg of GSSG is accommodated tightly via extensive interactions contributed by the N- and C-terminal lobes of GshT, while the GS-II leg extends to the solvent. This can explain the ligand promiscuity of GshT in terms of binding glutathione analogues with substitutions at the cysteine-sulfur or the glycine-carboxylate. Finally, we show that GshT primes glutathione import via the L-cystine ABC transporter TcyBC, a membrane permease, which had previously exclusively been associated with the transport of L-cystine.


    Organizational Affiliation

    Unit for Structural Biology, Laboratory for Protein Biochemistry and Biomolecular Engineering (L-ProBE), Ghent University, K. L. Ledeganckstraat 35, B-9000, Ghent, Belgium. bjorn.vergauwen@ugent.be




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PUTATIVE AMINO ACID BINDING PROTEIN
A, B
248Streptococcus mutansMutation(s): 0 
Gene Names: atmA
Find proteins for Q93DA5 (Streptococcus mutans)
Go to UniProtKB:  Q93DA5
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CL
Query on CL

Download SDF File 
Download CCD File 
A, B
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
GDS
Query on GDS

Download SDF File 
Download CCD File 
A, B
OXIDIZED GLUTATHIONE DISULFIDE
C20 H32 N6 O12 S2
YPZRWBKMTBYPTK-BJDJZHNGSA-N
 Ligand Interaction
CD
Query on CD

Download SDF File 
Download CCD File 
A, B
CADMIUM ION
Cd
WLZRMCYVCSSEQC-UHFFFAOYSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
GDSKd: 12200 nM BINDINGMOAD
GDSKd: 12200 nM PDBBIND
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.547 Å
  • R-Value Free: 0.183 
  • R-Value Work: 0.155 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 37.040α = 90.00
b = 103.120β = 92.31
c = 64.090γ = 90.00
Software Package:
Software NamePurpose
XDSdata scaling
XDSdata reduction
PHENIXrefinement
PHASERphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-08-21
    Type: Initial release
  • Version 1.1: 2013-08-28
    Type: Atomic model