2UVK | pdb_00002uvk

Structure of YjhT

• PDB DOI: https://doi.org/10.2210/pdb2UVK/pdb

• Classification: UNKNOWN FUNCTION
• Organism(s): Escherichia coli BL21
• Expression System: Escherichia coli BL21
• Mutation(s): No 


• Deposited: 2007-03-12 Released: 2007-12-04 
• Deposition Author(s): Muller, A., Severi, E., Wilson, K.S., Thomas, G.H.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.50 Å
• R-Value Free: 
  0.219 (Depositor), 0.220 (DCC) 
• R-Value Work: 
  0.180 (Depositor), 0.186 (DCC) 
• R-Value Observed: 
  0.182 (Depositor) 

Literature

Sialic Acid Mutarotation is Catalyzed by the Escherichia Coli Beta-Propeller Protein Yjht.

Severi, E., Muller, A., Potts, J.R., Leech, A., Williamson, D., Wilson, K.S., Thomas, G.H.

(2008) J Biological Chem 283: 4841

• PubMed: 18063573 
• DOI: https://doi.org/10.1074/jbc.M707822200
• Primary Citation Related Structures: 
  2UVK


• PubMed Abstract: 
  

  The acquisition of host-derived sialic acid is an important virulence factor for some bacterial pathogens, but in vivo this sugar acid is sequestered in sialoconjugates as the alpha-anomer. In solution, however, sialic acid is present mainly as the beta-anomer, formed by a slow spontaneous mutarotation. We studied the Escherichia coli protein YjhT as a member of a family of uncharacterized proteins present in many sialic acid-utilizing pathogens. This protein is able to accelerate the equilibration of the alpha- and beta-anomers of the sialic acid N-acetylneuraminic acid, thus describing a novel sialic acid mutarotase activity. The structure of this periplasmic protein, solved to 1.5A resolution, reveals a dimeric 6-bladed unclosed beta-propeller, the first of a bacterial Kelch domain protein. Mutagenesis of conserved residues in YjhT demonstrated an important role for Glu-209 and Arg-215 in mutarotase activity. We also present data suggesting that the ability to utilize alpha-N-acetylneuraminic acid released from complex sialoconjugates in vivo provides a physiological advantage to bacteria containing YjhT.

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Organizational Affiliation: 
• Department of Biology (Area 10), York Structural Biology Laboratory, University of York, York YO10 5YW, United Kingdom.

Biological Assembly 1  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 generated by PISA (software)

Macromolecule Content 

• Total Structure Weight: 77.75 kDa 
• Atom Count: 6,030 
• Modeled Residue Count: 691 
• Deposited Residue Count: 714 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
YJHT	A, B	357	Escherichia coli BL21	Mutation(s): 0  EC: 5.1.3.24
UniProt
Find proteins for P39371 (Escherichia coli (strain K12)) Explore P39371  Go to UniProtKB:  P39371

Small Molecules

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
MSE	A, B	L-PEPTIDE LINKING	C5 H11 N O2 Se		MET

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.50 Å
• R-Value Free:  0.219 (Depositor), 0.220 (DCC) 
• R-Value Work:  0.180 (Depositor), 0.186 (DCC) 
• R-Value Observed: 0.182 (Depositor) 

Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 44.758	α = 90
b = 105.659	β = 99.95
c = 74.222	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
MOSFLM	data reduction
SCALA	data scaling
SHELXCD	phasing
SHELXE	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2007-12-04 
Deposition Author(s): Muller, A., Severi, E., Wilson, K.S., Thomas, G.H.

Revision History  

• Version 1.0: 2007-12-04
  Type: Initial release
  
• Version 1.1: 2011-05-08
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2024-10-23
  Changes: Data collection, Database references, Derived calculations, Other, Structure summary