2X1I

glycoside hydrolase family 77 4-alpha-glucanotransferase from thermus brockianus


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.36 Å
  • R-Value Free: 0.240 
  • R-Value Work: 0.215 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural and Functional Analysis of Substrate Recognition by the 250S Loop in Amylomaltase from Thermus Brockianus.

Jung, J.-H.Jung, T.-Y.Seo, D.Yoon, S.-M.Choi, H.Park, B.C.Park, C.-S.Woo, E.-J.

(2011) Proteins 79: 633

  • DOI: 10.1002/prot.22911

  • PubMed Abstract: 
  • Amylomaltase, or 4-α-glucanotransferase (EC 2.4.1.25), is involved in glycogen and maltooligosaccharide metabolism in microorganisms, catalyzing both the hydrolysis and transfer of an α-1,4-oligosacchraride to other sugar molecules. In this study, we ...

    Amylomaltase, or 4-α-glucanotransferase (EC 2.4.1.25), is involved in glycogen and maltooligosaccharide metabolism in microorganisms, catalyzing both the hydrolysis and transfer of an α-1,4-oligosacchraride to other sugar molecules. In this study, we determined the crystal structure of amylomaltase from Thermus brockianus at a resolution of 2.3 Å and conducted a biochemical study to understand the detailed mechanism for its activity. Careful comparison with previous amylomaltase structures showed a pattern of conformational flexibility in the 250s loop with higher B-factor. Amylomaltase from T. brockianus exhibited a high transglycosylation factor for glucose and a lower value for maltose. Mutation of Gln256 resulted in increased K(m) for maltotriose and a sharp decrease of the transglycosylation factor for maltose, suggesting the involvement of Gln 256 in substrate binding between subsites +1 and +2. Mutation of Phe251 resulted in significantly lower glucose production but increased maltose production from maltopentose substrates, showing an altered substrate-binding affinity. The mutational data suggest the conformational flexibility of the loop may be involved in substrate binding in the GH77 family. Here, we present an action model of the 250s loop providing the molecular basis for the involvement of residues Phe251, Gln256, and Trp258 in the hydrolysis and transglycosylation activities in amylomaltase.


    Organizational Affiliation

    Graduate School of Biotechnology and Institute of Life Science and Resources, Kyung Hee University, Yongin 446-701, Korea.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
4-ALPHA-GLUCANOTRANSFERASE
A
500Thermus brockianusMutation(s): 0 
EC: 2.4.1.25
Find proteins for Q2VJA0 (Thermus brockianus)
Go to UniProtKB:  Q2VJA0
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PO4
Query on PO4

Download SDF File 
Download CCD File 
A
PHOSPHATE ION
O4 P
NBIIXXVUZAFLBC-UHFFFAOYSA-K
 Ligand Interaction
SO4
Query on SO4

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Download CCD File 
A
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
INS
Query on INS

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Download CCD File 
A
1,2,3,4,5,6-HEXAHYDROXY-CYCLOHEXANE
MYO-INOSITOL
C6 H12 O6
CDAISMWEOUEBRE-GPIVLXJGSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.36 Å
  • R-Value Free: 0.240 
  • R-Value Work: 0.215 
  • Space Group: P 65 2 2
Unit Cell:
Length (Å)Angle (°)
a = 104.357α = 90.00
b = 104.357β = 90.00
c = 263.759γ = 120.00
Software Package:
Software NamePurpose
PHASERphasing
CNSrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2010-10-27
    Type: Initial release
  • Version 1.1: 2011-08-31
    Type: Database references, Derived calculations, Refinement description, Version format compliance