1PC3

Crystal structure of the extracellular phosphate ABC transport receptor (PstS-1) and immunodominant antigen of M. tuberculosis.


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.16 Å
  • R-Value Free: 0.264 
  • R-Value Work: 0.220 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal structure of M tuberculosis ABC phosphate transport receptor: specificity and charge compensation dominated by ion-dipole interactions.

Vyas, N.K.Vyas, M.N.Quiocho, F.A.

(2003) Structure 11: 765-774


  • PubMed Abstract: 
  • The 2.16 A structure of the phosphate-bound PstS-1, the primary extracellular receptor for the ABC phosphate transporter and immunodominant species-specific antigen of Mycobacterium tuberculosis, has been determined. The phosphate, completely engulfe ...

    The 2.16 A structure of the phosphate-bound PstS-1, the primary extracellular receptor for the ABC phosphate transporter and immunodominant species-specific antigen of Mycobacterium tuberculosis, has been determined. The phosphate, completely engulfed in the cleft between two domains, is bound by 13 hydrogen bonds, 11 of which are formed with NH and OH dipolar donor groups. The further presence of two acidic residues, which serve as acceptors of the protonated phosphate, is key to conferring stringent specificity. The ion-dipole interactions between the phosphate and dipolar groups compensate the ligand's isolated negative charges. Moreover, the surprise finding that the electrostatic surface in and around the cleft is intensely negative demonstrates the power of ion-dipole interactions in anion binding and electrostatic balance. Additional functional features include both the flexible N-terminal segment that tethers PstS-1 on the cell surface and the hinge between the two domains, which should facilitate snaring the phosphate in the medium.


    Organizational Affiliation

    Verna and Marrs McLean Department, Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Phosphate-binding protein 1
A, B
350Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv)Gene Names: pstS1 (phoS1)
Find proteins for P9WGU1 (Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv))
Go to UniProtKB:  P9WGU1
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PO4
Query on PO4

Download SDF File 
Download CCD File 
A, B
PHOSPHATE ION
O4 P
NBIIXXVUZAFLBC-UHFFFAOYSA-K
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.16 Å
  • R-Value Free: 0.264 
  • R-Value Work: 0.220 
  • Space Group: P 21 21 2
Unit Cell:
Length (Å)Angle (°)
a = 125.400α = 90.00
b = 72.300β = 90.00
c = 73.400γ = 90.00
Software Package:
Software NamePurpose
SDMSdata scaling
STRATEGYdata reduction
PHASESphasing
CNSrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2004-05-18
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Source and taxonomy, Version format compliance