Biological Assembly 1  

 3D View: Structure | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Biological Assembly 2  

 3D View: Structure | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 2 assigned by authors.

Macromolecule Content

• Total Structure Weight: 71.83 kDa 
• Atom Count: 5098 
• Residue Count: 666 
• Unique protein chains: 1

1PC3

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

• DOI: 10.2210/pdb1PC3/pdb

• Classification: TRANSPORT PROTEIN
• Organism(s): Mycobacterium tuberculosis H37Rv
• Expression System: Escherichia coli K-12
• Mutation(s): No 


• Deposited: 2003-05-15 Released: 2004-05-18 
• Deposition Author(s): Vyas, N.K., Vyas, M.N., Quiocho, F.A.

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Experimental Data Snapshot

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

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: 12842040 
• DOI: 10.1016/s0969-2126(03)00109-6
• Structures With Same Primary Citation


• 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 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.

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Organizational Affiliation: 

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

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
Phosphate-binding protein 1	A, B	350	Mycobacterium tuberculosis H37Rv	Mutation(s): 0  Gene Names: PSTS1 OR PHOS1 OR RV0934 OR MT0961 OR MTCY08D9.05C, pstS1, phoS1, Rv0934, MTCY08D9.05c
Find proteins for P9WGU1 (Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv)) Explore P9WGU1  Go to UniProtKB:  P9WGU1

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
PO4	A, B	PHOSPHATE ION O4 P NBIIXXVUZAFLBC-UHFFFAOYSA-K

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.16 Å
• R-Value Free: 0.264 
• R-Value Work: 0.220 
• R-Value Observed: 0.220 
• Space Group: P 2₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 125.4	α = 90
b = 72.3	β = 90
c = 73.4	γ = 90

Software Package:

Software Name	Purpose
CNS	refinement
STRATEGY	data reduction
SDMS	data scaling
PHASES	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2003-05-15 
• Released Date: 2004-05-18 
Deposition Author(s): Vyas, N.K., Vyas, M.N., Quiocho, F.A.

Revision History 

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