1OCX

E. coli maltose-O-acetyltransferase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.15 Å
  • R-Value Free: 0.235 
  • R-Value Work: 0.194 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

The Structure and Specificity of Escherichia Coli Maltose Acetyltransferase Give New Insight Into the Laca Family of Acyltransferases.

Lo Leggio, L.Degan, F.D.Poulsen, P.Andersen, S.M.Larsen, S.

(2003) Biochemistry 42: 5225

  • DOI: 10.1021/bi0271446

  • PubMed Abstract: 
  • The crystallographic three-dimensional structure of the Escherichia coli maa gene product, previously identified as a maltose O-acetyltransferase (MAT) [Brand, B., and Boos, W. (1991) J. Biol. Chem. 266, 14113-14118] has been determined to 2.15 A res ...

    The crystallographic three-dimensional structure of the Escherichia coli maa gene product, previously identified as a maltose O-acetyltransferase (MAT) [Brand, B., and Boos, W. (1991) J. Biol. Chem. 266, 14113-14118] has been determined to 2.15 A resolution by the single anomalous dispersion method using data from a crystal cocrystallized with trimethyllead acetate. It is shown here that MAT acetylates glucose exclusively at the C6 position and maltose at the C6 position of the nonreducing end glucosyl moiety. Furthermore, MAT shows higher affinity toward artificial substrates containing an alkyl or hydrophobic chain as well as a glucosyl unit. The presence of a long hydrophobic patch near the acceptor site provides the structural explanation for this preference. The three-dimensional structure reveals the expected trimeric left-handed parallel beta-helix structure found in all other known hexapeptide repeat enzymes. In particular, the structure shows similarities both overall and at the putative active site to the recently determined structure of galactoside acetyltransferase (GAT), the lacA gene product [Wang, X.-G., Olsen, L. R., and Roderick, S. L. (2002) Structure 10, 581-588]. The structure, together with the new biochemical data, suggests that GAT and MAT are more closely related than previously thought and might have similar cellular functions. However, while GAT is specific for acetylation of galactosyl units, MAT is specific for glucosyl units and is able to acetylate maltooligosaccharides, an important property for biotechnological applications. Structural differences at the acceptor site reflect the differences in substrate specificity.


    Related Citations: 
    • Crystallization and Preliminary X-Ray Analysis of Maltose O-Acetyltransferase.
      Lo Leggio, L.,Dal Degan, F.,Poulsen, P.,Sorensen, S.O.,Harlow, K.,Harris, P.,Larsen, S.
      (2001) Acta Crystallogr.,Sect.D 57: 1915


    Organizational Affiliation

    Centre for Crystallographic Studies, Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen Ø, Denmark.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
MALTOSE O-ACETYLTRANSFERASE
A, B, C
182Escherichia coli (strain K12)Gene Names: maa (ylaD)
EC: 2.3.1.79
Find proteins for P77791 (Escherichia coli (strain K12))
Go to UniProtKB:  P77791
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PBM
Query on PBM

Download SDF File 
Download CCD File 
A, B, C
TRIMETHYL LEAD ION
C3 H9 Pb
SNBFOEGVGALPSE-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.15 Å
  • R-Value Free: 0.235 
  • R-Value Work: 0.194 
  • Space Group: C 2 2 21
Unit Cell:
Length (Å)Angle (°)
a = 64.623α = 90.00
b = 106.238β = 90.00
c = 175.433γ = 90.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
REFMACrefinement
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-06-12
    Type: Initial release
  • Version 1.1: 2014-09-03
    Type: Database references, Derived calculations, Non-polymer description, Other, Version format compliance