Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Standalone Viewers  
Protein Workshop | Ligand Explorer

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 58841.38 
• Atom Count: 4083 
• Residue Count: 519 
• Unique protein chains: 1

2EEX

Crystal structure of Cel44A, GH family 44 endoglucanase from Clostridium thermocellum

• DOI: 10.2210/pdb2EEX/pdb

• Classification: HYDROLASE
• Organism(s): Clostridium thermocellum (strain ATCC 27405 / DSM 1237 / NBRC 103400 / NCIMB 10682 / NRRL B-4536 / VPI 7372)
• Expression System: Escherichia coli
• Mutation(s): 1 


• Deposited: 2007-02-19 Released: 2007-09-18 
• Deposition Author(s): Kitago, Y., Karita, S., Watanabe, N., Sakka, K., Tanaka, I.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2 Å
• R-Value Free: 0.201 
• R-Value Work: 0.165 

Literature

Crystal structure of Cel44A, a glycoside hydrolase family 44 endoglucanase from Clostridium thermocellum.

Kitago, Y., Karita, S., Watanabe, N., Kamiya, M., Aizawa, T., Sakka, K., Tanaka, I.

(2007) J.Biol.Chem. 282: 35703-35711

• PubMed: 17905739 
• DOI: 10.1074/jbc.M706835200
• Primary Citation of Related Structures:  
  2EQD, 2EO7, 2EJ1, 2E4T, 2E0P


• PubMed Abstract: 
  

The crystal structure of Cel44A, which is one of the enzymatic components of the cellulosome of Clostridium thermocellum, was solved at a resolution of 0.96 A. This enzyme belongs to glycoside hydrolase family (GH family) 44. The structure reveals that Cel44A consists of a TIM-like barrel domain and a beta-sandwich domain. The wild-type and the E186Q mutant structures complexed with substrates suggest that two glutamic acid residues, Glu(186) and Glu(359), are the active residues of the enzyme. Biochemical experiments were performed to confirm this idea. The structural features indicate that GH family 44 belongs to clan GH-A and that the reaction catalyzed by Cel44A is retaining type hydrolysis. The stereochemical course of hydrolysis was confirmed by a (1)H NMR experiment using the reduced cellooligosaccharide as a substrate.

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Organizational Affiliation: 

Division of Biological Sciences, Graduate School of Science, Hokkaido University, Sapporo 0600810, Japan.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
Endoglucanase	A	519	Clostridium thermocellum (strain ATCC 27405 / DSM 1237 / NBRC 103400 / NCIMB 10682 / NRRL B-4536 / VPI 7372)	Mutation(s): 1
Find proteins for A3DD30 (Clostridium thermocellum (strain ATCC 27405 / DSM 1237 / NBRC 103400 / NCIMB 10682 / NRRL B-4536 / VPI 7372)) Go to UniProtKB:  A3DD30

Small Molecules

Ligands 5 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram & Interactions
ZN	A	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N
CL	A	CHLORIDE ION Cl VEXZGXHMUGYJMC-UHFFFAOYSA-M
CE5	A	CELLOPENTAOSE C30 H52 O26 FTNIPWXXIGNQQF-FFFJRYSISA-N
GOL	A	GLYCEROL GLYCERIN; PROPANE-1,2,3-TRIOL C3 H8 O3 PEDCQBHIVMGVHV-UHFFFAOYSA-N
CA	A	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2 Å
• R-Value Free: 0.201 
• R-Value Work: 0.165 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length (Å)	Angle (°)
a = 47.944	α = 90.00
b = 59.120	β = 90.00
c = 171.113	γ = 90.00

Software Package:

Software Name	Purpose
SCALEPACK	data scaling
CNS	refinement
DENZO	data reduction
ADSC	data collection
CNS	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2007-02-19 
• Released Date: 2007-09-18 
• Deposition Author(s): Kitago, Y., Karita, S., Watanabe, N., Sakka, K., Tanaka, I.

Revision History 

• Version 1.0: 2007-09-18
  Type: Initial release
• Version 1.1: 2011-07-13
  Type: Non-polymer description, Version format compliance