Crystal structure of ColD H188K S187N

Experimental Data Snapshot

  • Resolution: 2.20 Å
  • R-Value Free: 0.272 
  • R-Value Work: 0.177 
  • R-Value Observed: 0.180 

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This is version 1.5 of the entry. See complete history


Two Site-Directed Mutations Are Required for the Conversion of a Sugar Dehydratase into an Aminotransferase.

Cook, P.D.Kubiak, R.L.Toomey, D.P.Holden, H.M.

(2009) Biochemistry 48: 5246-5253

  • DOI: https://doi.org/10.1021/bi9005545
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    L-colitose and d-perosamine are unusual sugars found in the O-antigens of some Gram-negative bacteria such as Escherichia coli, Vibrio cholerae, and Salmonella enterica, among others. The biosynthetic pathways for these two sugars begin with the formation of GDP-mannose from d-mannose 1-phosphate and GTP followed by the subsequent dehydration and oxidation of GDP-mannose to yield GDP-4-keto-6-deoxymannose. Following the production of GDP-4-keto-6-deoxymannose, the two pathways diverge. In the case of GDP-perosamine biosynthesis, the next step involves an amination reaction at the C-4' position of the sugar, whereas in GDP-colitose production, the 3'-hydroxyl group is removed. The enzymes catalyzing these reactions are GDP-perosamine synthase and GDP-4-keto-6-deoxymannose-3-dehydratase (ColD), respectively. Both of these enzymes are pyridoxal 5'-phosphate (PLP) dependent, and their three-dimensional structures place them into the well-characterized aspartate aminotransferase superfamily. A comparison of the active site architecture of ColD from E. coli (strain 5a, type O55:H7) to that of GDP-perosamine synthase from Caulobacter crescentus CB15 suggested that only two mutations would be required to convert ColD into an aminotransferase. Here we present a combined structural and functional analysis of the ColD S187N/H188K mutant protein that, indeed, has been converted from a sugar dehydratase into an aminotransferase.

  • Organizational Affiliation

    Department of Biochemistry, University of Wisconsin, Madison, Wisconsin 53706, USA.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
A, B, C, D, E
A, B, C, D, E, F, G, H
390Escherichia coliMutation(s): 2 
Gene Names: wbdK
Find proteins for B1B4V9 (Escherichia coli O55:H6)
Explore B1B4V9 
Go to UniProtKB:  B1B4V9
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupB1B4V9
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 2.20 Å
  • R-Value Free: 0.272 
  • R-Value Work: 0.177 
  • R-Value Observed: 0.180 
  • Space Group: P 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 69.728α = 78.98
b = 114.659β = 76.23
c = 114.568γ = 76.33
Software Package:
Software NamePurpose
PROTEUM PLUSdata collection
SAINTdata reduction
SADABSdata scaling

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2009-06-16
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Non-polymer description, Version format compliance
  • Version 1.2: 2017-05-03
    Changes: Non-polymer description
  • Version 1.3: 2021-10-20
    Changes: Database references, Derived calculations
  • Version 1.4: 2023-09-06
    Changes: Data collection, Refinement description
  • Version 1.5: 2023-11-22
    Changes: Data collection