Crystal structure of aldose-aldose oxidoreductase from Caulobacter crescentus complexed with maltotriose

Experimental Data Snapshot

  • Resolution: 1.90 Å
  • R-Value Free: 0.178 
  • R-Value Work: 0.152 
  • R-Value Observed: 0.153 

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Structure and Function of Caulobacter Crescentus Aldose-Aldose Oxidoreductase.

Taberman, H.Andberg, M.Koivula, A.Hakulinen, N.Penttila, M.Rouvinen, J.Parkkinen, T.

(2015) Biochem J 472: 297

  • DOI: https://doi.org/10.1042/BJ20150681
  • Primary Citation of Related Structures:  
    5A02, 5A03, 5A04, 5A05, 5A06

  • PubMed Abstract: 

    Aldose-aldose oxidoreductase (Cc AAOR) is a recently characterized enzyme from the bacterial strain Caulobacter crescentus CB15 belonging to the glucose-fructose oxidoreductase/inositol dehydrogenase/rhizopine catabolism protein (Gfo/Idh/MocA) family. Cc AAOR catalyses the oxidation and reduction of a panel of aldose monosaccharides using a tightly bound NADP(H) cofactor that is regenerated in the catalytic cycle. Furthermore, Cc AAOR can also oxidize 1,4-linked oligosaccharides. In the present study, we present novel crystal structures of the dimeric Cc AAOR in complex with the cofactor and glycerol, D-xylose, D-glucose, maltotriose and D-sorbitol determined to resolutions of 2.0, 1.8, 1.7, 1.9 and 1.8 Å (1 Å=0.1 nm), respectively. These complex structures allowed for a detailed analysis of the ligand-binding interactions. The structures showed that the C1 carbon of a substrate, which is either reduced or oxidized, is close to the reactive C4 carbon of the nicotinamide ring of NADP(H). In addition, the O1 hydroxy group of the substrate, which is either protonated or deprotonated, is unexpectedly close to both Lys(104) and Tyr(189), which may both act as a proton donor or acceptor. This led us to hypothesize that this intriguing feature could be beneficial for Cc AAOR to catalyse the reduction of a linear form of a monosaccharide substrate and the oxidation of a pyranose form of the same substrate in a reaction cycle, during which the bound cofactor is regenerated.

  • Organizational Affiliation

    Department of Chemistry, University of Eastern Finland, PO Box 111, FI-80101 Joensuu, Finland.

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
339Caulobacter vibrioides CB15Mutation(s): 0 
EC: 1.1.99
Find proteins for Q9A8X3 (Caulobacter vibrioides (strain ATCC 19089 / CB15))
Explore Q9A8X3 
Go to UniProtKB:  Q9A8X3
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ9A8X3
Sequence Annotations
  • Reference Sequence


Entity ID: 2
MoleculeChains Length2D Diagram Glycosylation3D Interactions
G, H, I, J
Glycosylation Resources
GlyTouCan:  G00395FS
GlyCosmos:  G00395FS
GlyGen:  G00395FS
Small Molecules
Ligands 2 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
Query on NDP

Download Ideal Coordinates CCD File 
K [auth A]
L [auth B]
O [auth C]
P [auth D]
Q [auth E]
K [auth A],
L [auth B],
O [auth C],
P [auth D],
Q [auth E],
R [auth F]
C21 H30 N7 O17 P3
Query on MLI

Download Ideal Coordinates CCD File 
M [auth B],
N [auth B],
S [auth F]
C3 H2 O4
Experimental Data & Validation

Experimental Data

  • Resolution: 1.90 Å
  • R-Value Free: 0.178 
  • R-Value Work: 0.152 
  • R-Value Observed: 0.153 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 100.295α = 90
b = 151.321β = 108.66
c = 108.693γ = 90
Software Package:
Software NamePurpose
XDSdata reduction

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2015-10-21
    Type: Initial release
  • Version 1.1: 2015-12-09
    Changes: Database references
  • Version 2.0: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Atomic model, Data collection, Derived calculations, Other, Structure summary
  • Version 2.1: 2024-01-10
    Changes: Data collection, Database references, Refinement description, Structure summary