1PSZ | pdb_00001psz

PNEUMOCOCCAL SURFACE ANTIGEN PSAA

• PDB DOI: https://doi.org/10.2210/pdb1PSZ/pdb

• Classification: IMMUNE SYSTEM
• Organism(s): Streptococcus pneumoniae
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 1998-10-13 Released: 2000-04-19 
• Deposition Author(s): Lawrence, M.C., Pilling, P.A., Epa, V.C., Berry, A.M., Ogunniyi, A.D., Paton, J.C.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Free: 
  0.236 (Depositor) 
• R-Value Work: 
  0.178 (Depositor), 0.181 (DCC) 

Literature

The crystal structure of pneumococcal surface antigen PsaA reveals a metal-binding site and a novel structure for a putative ABC-type binding protein.

Lawrence, M.C., Pilling, P.A., Epa, V.C., Berry, A.M., Ogunniyi, A.D., Paton, J.C.

(1998) Structure 6: 1553-1561

• PubMed: 9862808 
• DOI: https://doi.org/10.1016/s0969-2126(98)00153-1
• Primary Citation Related Structures: 
  1PSZ


• PubMed Abstract: 
  

  . The surface protein PsaA of the pathogenic bacterium Streptococcus pneumoniae plays an essential role in its virulence. PsaA is a putative ATP-binding cassette-type (ABC-type) binding protein involved in the uptake of Mn2+ and possibly Zn2+ and is considered to be both a potential drug target and and a candidate vaccine component. . The structure of PsaA has been determined to 2.0 A resolution using X-ray crystallography and is the first structure obtained for an ABC-type binding protein from a Gram-positive organism. The protein consists of two (beta/alpha)4 domains linked together by a single helix. A metal-binding site is formed in the domain interface by the sidechains of His67, His139, Glu205 and Asp280 and is occupied in the structure. . The structural topology of PsaA is fundamentally different from that of other ABC-type binding proteins determined thus far in that PsaA lacks the characteristic 'hinge peptides' involved in conformational change upon solute uptake and release. In our structure, the metal-binding site is probably occupied by Zn2+. The site seems to be well conserved amongst related receptors from both Gram-positive and Gram-negative bacteria.

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Organizational Affiliation: 
• Biomolecular Research Institute 343 Royal Parade Parkville Victoria 3052 Australia. [e-mail]

Biological Assembly 1  

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

Biological assembly 1 assigned by authors.

Macromolecule Content 

• Total Structure Weight: 34.21 kDa 
• Atom Count: 2,502 
• Modeled Residue Count: 286 
• Deposited Residue Count: 303 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PROTEIN (SURFACE ANTIGEN PSAA)	A	303	Streptococcus pneumoniae	Mutation(s): 0
UniProt
Find proteins for P0A4G2 (Streptococcus pneumoniae serotype 4 (strain ATCC BAA-334 / TIGR4)) Explore P0A4G2  Go to UniProtKB:  P0A4G2

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
ZN	B [auth A]	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Free:  0.236 (Depositor) 
• R-Value Work:  0.178 (Depositor), 0.181 (DCC) 

Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 60.024	α = 90
b = 66.517	β = 90
c = 69.838	γ = 90

Software Package:

Software Name	Purpose
SHARP	phasing
REFMAC	refinement
DENZO	data reduction
SCALEPACK	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2000-04-19 
Deposition Author(s): Lawrence, M.C., Pilling, P.A., Epa, V.C., Berry, A.M., Ogunniyi, A.D., Paton, J.C.

Revision History  

• Version 1.0: 2000-04-19
  Type: Initial release
  
• Version 1.1: 2007-10-16
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2018-04-04
  Changes: Data collection
• Version 1.4: 2023-12-27
  Changes: Data collection, Database references, Derived calculations