1CEC | pdb_00001cec

A COMMON PROTEIN FOLD AND SIMILAR ACTIVE SITE IN TWO DISTINCT FAMILIES OF BETA-GLYCANASES

• PDB DOI: https://doi.org/10.2210/pdb1CEC/pdb

• Classification: HYDROLASE (GLYCOSYL)
• Organism(s): Acetivibrio thermocellus
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 1995-06-07 Released: 1996-01-29 
• Deposition Author(s): Alzari, P.M., Dominguez, R.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.15 Å
• R-Value Free: 
  0.215 (Depositor) 
• R-Value Work: 
  0.168 (Depositor) 
• R-Value Observed: 
  0.168 (Depositor) 

Literature

A common protein fold and similar active site in two distinct families of beta-glycanases.

Dominguez, R., Souchon, H., Spinelli, S., Dauter, Z., Wilson, K.S., Chauvaux, S., Beguin, P., Alzari, P.M.

(1995) Nat Struct Biol 2: 569-576

• PubMed: 7664125 
• DOI: https://doi.org/10.1038/nsb0795-569
• Primary Citation Related Structures: 
  1CEC, 1XYZ


• PubMed Abstract: 
  

  The structure of Clostridium thermocellum endoglucanase CelC, a member of the largest cellulase family (family A), has been determined at 2.15 A resolution. The protein folds into an (alpha/beta)8 barrel, with a deep active-site cleft generated by the insertion of a helical subdomain. The structure of the catalytic core of xylanase XynZ, which belongs to xylanase family F, has been determined at 1.4 A resolution. In spite of significant differences in substrate specificity and structure (including the absence of the helical subdomain), the general polypeptide folding pattern, architecture of the active site and catalytic mechanism of XynZ and CelC are similar, suggesting a common evolutionary origin.

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Organizational Affiliation: 
• Unité d'Immunologie Structurale, URA 1961 CNRS, Institute Pasteur, Paris, France.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content 

• Total Structure Weight: 40.95 kDa 
• Atom Count: 2,942 
• Modeled Residue Count: 331 
• Deposited Residue Count: 343 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
ENDOGLUCANASE CELC	A	343	Acetivibrio thermocellus	Mutation(s): 0  Gene Names: MC1061 EC: 3.2.1.4
UniProt
Find proteins for P0C2S3 (Acetivibrio thermocellus) Explore P0C2S3  Go to UniProtKB:  P0C2S3

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.15 Å
• R-Value Free:  0.215 (Depositor) 
• R-Value Work:  0.168 (Depositor) 
• R-Value Observed: 0.168 (Depositor) 

Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 51.4	α = 90
b = 84.33	β = 90
c = 87.5	γ = 90

Software Package:

Software Name	Purpose
ARP/wARP	model building
X-PLOR	model building
X-PLOR	refinement
DENZO	data reduction
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 1996-01-29 
Deposition Author(s): Alzari, P.M., Dominguez, R.

Revision History  

• Version 1.0: 1996-01-29
  Type: Initial release
  
• Version 1.1: 2008-03-24
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2024-02-07
  Changes: Data collection, Database references