3NSN

Crystal Structure of insect beta-N-acetyl-D-hexosaminidase OfHex1 complexed with TMG-chitotriomycin


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Work: 0.202 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural Determinants of an Insect {beta}-N-Acetyl-D-hexosaminidase Specialized as a Chitinolytic Enzyme

Liu, T.Zhang, H.Liu, F.Wu, Q.Shen, X.Yang, Q.

(2011) J.Biol.Chem. 286: 4049-4058

  • DOI: 10.1074/jbc.M110.184796
  • Primary Citation of Related Structures:  3NSM

  • PubMed Abstract: 
  • β-N-acetyl-D-hexosaminidase has been postulated to have a specialized function. However, the structural basis of this specialization is not yet established. OfHex1, the enzyme from the Asian corn borer Ostrinia furnacalis (one of the most destructive ...

    β-N-acetyl-D-hexosaminidase has been postulated to have a specialized function. However, the structural basis of this specialization is not yet established. OfHex1, the enzyme from the Asian corn borer Ostrinia furnacalis (one of the most destructive pests) has previously been reported to function merely in chitin degradation. Here the vital role of OfHex1 during the pupation of O. furnacalis was revealed by RNA interference, and the crystal structures of OfHex1 and OfHex1 complexed with TMG-chitotriomycin were determined at 2.1 Å. The mechanism of selective inhibition by TMG-chitotriomycin was related to the existence of the +1 subsite at the active pocket of OfHex1 and a key residue, Trp(490), at this site. Mutation of Trp(490) to Ala led to a 2,277-fold decrease in sensitivity toward TMG-chitotriomycin as well as an 18-fold decrease in binding affinity for the substrate (GlcNAc)(2). Although the overall topology of the catalytic domain of OfHex1 shows a high similarity with the human and bacterial enzymes, OfHex1 is distinguished from these enzymes by large conformational changes linked to an "open-close" mechanism at the entrance of the active site, which is characterized by the "lid" residue, Trp(448). Mutation of Trp(448) to Ala or Phe resulted in a more than 1,000-fold loss in enzyme activity, due mainly to the effect on k(cat). The current work has increased our understanding of the structure-function relationship of OfHex1, shedding light on the structural basis that accounts for the specialized function of β-N-acetyl-D-hexosaminidase as well as making the development of species-specific pesticides a likely reality.


    Organizational Affiliation

    Department of Bioscience and Biotechnology, Dalian University of Technology, Dalian 116024, China.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
N-acetylglucosaminidase
A
572Ostrinia furnacalisEC: 3.2.1.52
Find proteins for Q06GJ0 (Ostrinia furnacalis)
Go to UniProtKB:  Q06GJ0
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CTO
Query on CTO

Download SDF File 
Download CCD File 
A
TRIACETYLCHITOTRIOSE
CHITOTRIOSE
C24 H41 N3 O16
WZZVUHWLNMNWLW-VFCSDQTKSA-N
 Ligand Interaction
TMX
Query on TMX

Download SDF File 
Download CCD File 
A
2-deoxy-2-(trimethylammonio)-beta-D-glucopyranose
C9 H20 N O5
SYZAECJPHGGBMC-JGKVKWKGSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Work: 0.202 
  • Space Group: P 32 2 1
Unit Cell:
Length (Å)Angle (°)
a = 108.500α = 90.00
b = 108.500β = 90.00
c = 175.570γ = 120.00
Software Package:
Software NamePurpose
HKL-2000data scaling
CNSphasing
HKL-2000data collection
CNSrefinement
REFMACrefinement
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2010-11-24
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance