1OBB

alpha-glucosidase A, AglA, from Thermotoga maritima in complex with maltose and NAD+

Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.235 
  • R-Value Work: 0.199 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history. 

Literature

Crystal Structure of Thermotoga Maritima Alpha-Glucosidase Agla Defines a New Clan of Nad+-Dependent Glycosidases

Lodge, J.A., Maier, T., Liebl, W., Hoffmann, V., Strater, N.

(2003) J.Biol.Chem. 278: 19151

  • DOI: 10.1074/jbc.M211626200

  • PubMed Abstract: 

    • Glycoside hydrolase family 4 represents an unusual group of glucosidases with a requirement for NAD+, divalent metal cations, and reducing conditions. The family is also unique in its inclusion of both alpha- and beta-specific enzymes. The alpha-gluc ...

    Glycoside hydrolase family 4 represents an unusual group of glucosidases with a requirement for NAD+, divalent metal cations, and reducing conditions. The family is also unique in its inclusion of both alpha- and beta-specific enzymes. The alpha-glucosidase A, AglA, from Thermotoga maritima is a typical glycoside hydrolase family 4 enzyme, requiring NAD+ and Mn2+ as well as strongly reducing conditions for activity. Here we present the crystal structure of the protein complexed with NAD+ and maltose, refined at a resolution of 1.9 A. The NAD+ is bound to a typical Rossman fold NAD+-binding site, and the nicotinamide moiety is localized close to the maltose substrate. Within the active site the conserved Cys-174 and surrounding histidines are positioned to play a role in the hydrolysis reaction. The electron density maps indicate that Cys-174 is oxidized to a sulfinic acid. Most likely, the strongly reducing conditions are necessary to reduce the oxidized cysteine side chain. Notably, the canonical set of catalytic acidic residues common to other glucosidases is not present in the active site. This, combined with a high structural homology to NAD-dependent dehydrogenases, suggests an unusual and possibly unique mechanism of action for a glycoside-hydrolyzing enzyme.

    Organizational Affiliation: 

    Institut für Chemie, Takustrasse 6, Freie Universität Berlin, D-14195 Berlin.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
ALPHA-GLUCOSIDASE
A, B
480Thermotoga maritima (strain ATCC 43589 / MSB8 / DSM 3109 / JCM 10099)Mutation(s): 0 
Gene Names: aglA
EC: 3.2.1.20
Find proteins for O33830 (Thermotoga maritima (strain ATCC 43589 / MSB8 / DSM 3109 / JCM 10099))
Go to UniProtKB:  O33830
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MAL
Query on MAL
Download SDF File 
Download CCD File 
A, B
MALTOSE
C12 H22 O11
GUBGYTABKSRVRQ-ASMJPISFSA-N
 Ligand Interaction
NAD
Query on NAD
Download SDF File 
Download CCD File 
A, B
NICOTINAMIDE-ADENINE-DINUCLEOTIDE
C21 H27 N7 O14 P2
BAWFJGJZGIEFAR-NNYOXOHSSA-N
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
CSD
Query on CSD
A, B
L-PEPTIDE LINKINGC3 H7 N O4 SCYS
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.235 
  • R-Value Work: 0.199 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 75.000α = 90.00
b = 85.700β = 106.00
c = 83.600γ = 90.00
Software Package:
Software NamePurpose
CNSrefinement
SCALEPACKdata scaling
SHARPphasing
DENZOdata reduction

Structure Validation

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Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-05-21
    Type: Initial release
  • Version 1.1: 2014-11-05
    Type: Atomic model, Derived calculations, Non-polymer description, Other, Structure summary, Version format compliance