2XXK

SiaP complex

• PDB DOI: https://doi.org/10.2210/pdb2XXK/pdb

• Classification: TRANSPORT PROTEIN
• Organism(s): Haemophilus influenzae
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): Yes 


• Deposited: 2010-11-10 Released: 2011-11-23 
• Deposition Author(s): Fischer, M., Hubbard, R.E.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.48 Å
• R-Value Free: 0.153 
• R-Value Work: 0.106 
• R-Value Observed: 0.108 

Starting Model: experimental

Literature

Siap Complex

Hopkins, A.P., Fischer, M., Hawkhead, J., Hubbard, R.E., Thomas, G.H.

To be published.

Biological Assembly 1  

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

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 35.34 kDa 
• Atom Count: 3,038 
• Modelled Residue Count: 308 
• Deposited Residue Count: 312 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
SIALIC ACID-BINDING PERIPLASMIC PROTEIN SIAP	A	312	Haemophilus influenzae	Mutation(s): 1
UniProt
Find proteins for P44542 (Haemophilus influenzae (strain ATCC 51907 / DSM 11121 / KW20 / Rd)) Explore P44542  Go to UniProtKB:  P44542

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SLB	B [auth A]	N-acetyl-beta-neuraminic acid C11 H19 N O9 SQVRNKJHWKZAKO-PFQGKNLYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.48 Å
• R-Value Free: 0.153 
• R-Value Work: 0.106 
• R-Value Observed: 0.108 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 47.7	α = 90
b = 74.74	β = 90
c = 87.07	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
MOSFLM	data reduction
SCALEPACK	data scaling
REFMAC	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2011-11-23 
Deposition Author(s): Fischer, M., Hubbard, R.E.

Revision History  

• Version 1.0: 2011-11-23
  Type: Initial release
  
• Version 1.1: 2019-03-06
  Changes: Data collection, Experimental preparation, Other
• Version 1.2: 2020-07-29
  Type: Remediation
  Reason: Carbohydrate remediation
  Changes: Data collection, Derived calculations, Other, Structure summary
• Version 1.3: 2023-12-20
  Changes: Data collection, Database references, Refinement description, Structure summary