2X2I

Crystal structure of the Gracilariopsis lemaneiformis alpha-1,4- glucan lyase with acarbose


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.60 Å
  • R-Value Free: 0.320 
  • R-Value Work: 0.229 
  • R-Value Observed: 0.234 

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This is version 2.0 of the entry. See complete history


Literature

Crystal Structure of Alpha-1,4-Glucan Lyase, a Unique Glycoside Hydrolase Family Member with a Novel Catalytic Mechanism.

Rozeboom, H.J.Yu, S.Madrid, S.Kalk, K.H.Zhang, R.Dijkstra, B.W.

(2013) J Biol Chem 288: 26764

  • DOI: 10.1074/jbc.M113.485896
  • Primary Citation of Related Structures:  
    2X2H, 2X2I, 2X2J, 4AMW, 4AMX

  • PubMed Abstract: 
  • α-1,4-Glucan lyase (EC 4.2.2.13) from the red seaweed Gracilariopsis lemaneiformis cleaves α-1,4-glucosidic linkages in glycogen, starch, and malto-oligosaccharides, yielding the keto-monosaccharide 1,5-anhydro-D-fructose. The enzyme belongs to glycoside hydrolase family 31 (GH31) but degrades starch via an elimination reaction instead of hydrolysis ...

    α-1,4-Glucan lyase (EC 4.2.2.13) from the red seaweed Gracilariopsis lemaneiformis cleaves α-1,4-glucosidic linkages in glycogen, starch, and malto-oligosaccharides, yielding the keto-monosaccharide 1,5-anhydro-D-fructose. The enzyme belongs to glycoside hydrolase family 31 (GH31) but degrades starch via an elimination reaction instead of hydrolysis. The crystal structure shows that the enzyme, like GH31 hydrolases, contains a (β/α)8-barrel catalytic domain with B and B' subdomains, an N-terminal domain N, and the C-terminal domains C and D. The N-terminal domain N of the lyase was found to bind a trisaccharide. Complexes of the enzyme with acarbose and 1-dexoynojirimycin and two different covalent glycosyl-enzyme intermediates obtained with fluorinated sugar analogues show that, like GH31 hydrolases, the aspartic acid residues Asp(553) and Asp(665) are the catalytic nucleophile and acid, respectively. However, as a unique feature, the catalytic nucleophile is in a position to act also as a base that abstracts a proton from the C2 carbon atom of the covalently bound subsite -1 glucosyl residue, thus explaining the unique lyase activity of the enzyme. One Glu to Val mutation in the active site of the homologous α-glucosidase from Sulfolobus solfataricus resulted in a shift from hydrolytic to lyase activity, demonstrating that a subtle amino acid difference can promote lyase activity in a GH31 hydrolase.


    Organizational Affiliation

    From the Laboratory of Biophysical Chemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
ALPHA-1,4-GLUCAN LYASE ISOZYME 1A, B, C, D1,027Gracilariopsis lemaneiformisMutation(s): 0 
Gene Names: Ag111
EC: 4.2.2.13
UniProt
Find proteins for Q9STC1 (Gracilariopsis lemaneiformis)
Explore Q9STC1 
Go to UniProtKB:  Q9STC1
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ9STC1
Protein Feature View
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  • Reference Sequence
Oligosaccharides

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Entity ID: 2
MoleculeChainsChain Length2D DiagramGlycosylation3D Interactions
4,6-dideoxy-4-{[(1S,4R,5S,6S)-4,5,6-trihydroxy-3-(hydroxymethyl)cyclohex-2-en-1-yl]amino}-alpha-D-glucopyranose-(1-4)-alpha-D-glucopyranose-(1-4)-beta-D-glucopyranose
E, F, G, H, I, J, K, L
E, F, G, H, I, J, K, L
3N/AN/A Oligosaccharides Interaction
Glycosylation Resources
GlyTouCan:  G08743RW
GlyCosmos:  G08743RW
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
CSO
Query on CSO
A, B, C, D L-PEPTIDE LINKINGC3 H7 N O3 SCYS
Biologically Interesting Molecules (External Reference) 1 Unique
Entity ID: 2
IDChainsNameType/Class2D Diagram3D Interactions
PRD_900022
Query on PRD_900022
E, F, G, H, I, J, K, Lbeta-acarboseOligosaccharide / Inhibitor Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.60 Å
  • R-Value Free: 0.320 
  • R-Value Work: 0.229 
  • R-Value Observed: 0.234 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 134.861α = 90
b = 91.804β = 99.34
c = 193.349γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
DENZOdata reduction
SCALEPACKdata scaling
PHASERphasing

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2011-01-19
    Type: Initial release
  • Version 1.1: 2013-08-14
    Changes: Database references, Derived calculations, Non-polymer description, Version format compliance
  • Version 1.2: 2013-09-25
    Changes: Database references
  • Version 1.3: 2017-07-05
    Changes: Data collection
  • Version 1.4: 2019-01-30
    Changes: Data collection, Experimental preparation
  • Version 1.5: 2019-02-06
    Changes: Data collection, Experimental preparation
  • Version 2.0: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Advisory, Atomic model, Data collection, Derived calculations, Non-polymer description, Other, Structure summary