6H75

SiaP A11N in complex with Neu5Ac (RT)

• PDB DOI: https://doi.org/10.2210/pdb6H75/pdb

• Classification: TRANSPORT PROTEIN
• Organism(s): Haemophilus influenzae Rd KW20
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): Yes 


• Deposited: 2018-07-30 Released: 2019-08-14 
• Deposition Author(s): Fischer, M., Darby, J.F., Brannigan, J.A., Turkenburg, J., Hubbard, R.E.
• Funding Organization(s): Biotechnology and Biological Sciences Research Council

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.45 Å
• R-Value Free: 0.146 
• R-Value Work: 0.109 
• R-Value Observed: 0.111 

Biological Assembly 1  

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

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

Biological Assembly Evidence: gel filtration

Macromolecule Content

• Total Structure Weight: 35.38 kDa 
• Atom Count: 2,959 
• 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 Rd KW20	Mutation(s): 1  Gene Names: siaP, HI_0146
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 (Subject of Investigation/LOI)	B [auth A]	N-acetyl-beta-neuraminic acid C11 H19 N O9 SQVRNKJHWKZAKO-PFQGKNLYSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
SLB	Binding MOAD:  6H75	Kd: 4.20e+4 (nM) from 1 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.45 Å
• R-Value Free: 0.146 
• R-Value Work: 0.109 
• R-Value Observed: 0.111 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 48.173	α = 90
b = 75.485	β = 90
c = 88.223	γ = 90

Software Package:

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

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2019-08-14 
Deposition Author(s): Fischer, M., Darby, J.F., Brannigan, J.A., Turkenburg, J., Hubbard, R.E.

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Funding Organization	Location	Grant Number
Biotechnology and Biological Sciences Research Council	United Kingdom	BBC509807

Revision History  

• Version 1.0: 2019-08-14
  Type: Initial release
  
• Version 1.1: 2019-09-25
  Changes: Data collection, Database references
• Version 1.2: 2019-10-16
  Changes: Data collection, Database references
• Version 1.3: 2020-07-29
  Type: Remediation
  Reason: Carbohydrate remediation
  Changes: Data collection, Derived calculations, Structure summary