Chitinase ChiA74 from Bacillus thuringiensis

Experimental Data Snapshot

  • Resolution: 2.26 Å
  • R-Value Free: 0.253 
  • R-Value Work: 0.239 
  • R-Value Observed: 0.240 

wwPDB Validation   3D Report Full Report

This is version 1.2 of the entry. See complete history


The crystal structure of the chitinase ChiA74 of Bacillus thuringiensis has a multidomain assembly.

Juarez-Hernandez, E.O.Casados-Vazquez, L.E.Brieba, L.G.Torres-Larios, A.Jimenez-Sandoval, P.Barboza-Corona, J.E.

(2019) Sci Rep 9: 2591-2591

  • DOI: https://doi.org/10.1038/s41598-019-39464-z
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    There is no structural information about any chitinase synthesized by Bacillus thuringiensis, the most successful microbial insect larvicide used worldwide. In this study, we solved the 3D structure of the chitinase ChiA74 at 2.26 Å. The crystal structure shows that ChiA74 is composed of a modular arrangement formed by (i) a catalytic region (CD), (ii) a chitinase insertion domain (CID), (iii) a fibronectin type III domain (FnIII), and (iv) a chitin binding domain (CBD). The location of the CBD with respect to the CD has no structural similarity to other chitinases with known structures. The activity of a ChiA74 lacking its secretion signal peptide (ChiA74Δsp) and a truncated version lacking its CBD/FnIII domains (ChiA74Δsp-50) did not have statistical differences in activity against colloidal chitin. However, ChiA74Δsp exhibits 4.5 and 2.0 higher activity than versions lacking the CBD (ChiA74Δsp-60) and CBD/FnIII domains (ChiA74Δsp-50), respectively, when crystalline chitin was used as substrate. Our data suggest that the CBD might plays a significant role in crystalline chitin hydrolysis. We also demonstrated the importance of the catalytic E211 in the CD, as mutants ChiA74Δsp E211N and ChiA74Δsp D207N, E211N were inactive against colloidal and crystalline chitins, chitosan and 4-MU-GlcNAc 3 . ChiA74 has a processive activity producing oligosaccharides with degree of polymerization (DP) of 1 (GlcNAc) and 2 (GlcNAc 2 ).

  • Organizational Affiliation

    Universidad de Guanajuato Campus Irapuato-Salamanca, División de Ciencias de la Vida, Posgrado en Biociencias, Irapuato, Guanajuato, 36500, Mexico.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
A, B
672Bacillus thuringiensisMutation(s): 0 
Gene Names: BK774_19500
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 2.26 Å
  • R-Value Free: 0.253 
  • R-Value Work: 0.239 
  • R-Value Observed: 0.240 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 85.827α = 90
b = 82.407β = 108.11
c = 101.57γ = 90
Software Package:
Software NamePurpose
Aimlessdata scaling
PDB_EXTRACTdata extraction
DIALSdata reduction

Structure Validation

View Full Validation Report

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2019-03-06
    Type: Initial release
  • Version 1.1: 2019-11-06
    Changes: Author supporting evidence, Data collection
  • Version 1.2: 2023-10-04
    Changes: Data collection, Database references, Refinement description