Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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

Biological assembly 1 assigned by authors and generated by PQS (software)

Macromolecule Content

• Total Structure Weight: 18.81 kDa 
• Atom Count: 1607 
• Modelled Residue Count: 153 
• Deposited Residue Count: 153 
• Unique protein chains: 1

1GWM

Carbohydrate binding module family29 complexed with glucohexaose

• DOI: 10.2210/pdb1GWM/pdb

• Classification: CARBOHYDRATE BINDING DOMAIN
• Organism(s): Piromyces sp. 'equi
• Expression System: Escherichia coli BL21
• Mutation(s): No 


• Deposited: 2002-03-19 Released: 2003-03-20 
• Deposition Author(s): Charnock, S.J., Nurizzo, D., Davies, G.J.

---

Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.15 Å
• R-Value Free: 0.156 
• R-Value Work: 0.128 
• R-Value Observed: 0.129 

Literature

Promiscuity in Ligand-Binding: The Three-Dimensional Structure of a Piromyces Carbohydrate-Binding Module,Cbm29-2,in Complex with Cello- and Mannohexaose

Charnock, S.J., Bolam, D., Nurizzo, D., Szabo, L., Mckie, V., Gilbert, H., Davies, G.J.

(2002) Proc Natl Acad Sci U S A 99: 14077

• PubMed: 12391332 
• DOI: 10.1073/pnas.212516199
• Primary Citation of Related Structures:  
  1GWM, 1GWL, 1GWK


• PubMed Abstract: 
  

Carbohydrate-protein recognition is central to many biological processes. Enzymes that act on polysaccharide substrates frequently contain noncatalytic domains, "carbohydrate-binding modules" (CBMs), that target the enzyme to the appropriate substrate. CBMs that recognize specific plant structural polysaccharides are often able to accommodate both the variable backbone and the side-chain decorations of heterogeneous ligands. "CBM29" modules, derived from a noncatalytic component of the Piromyces equi cellulase/hemicellulase complex, provide an example of this selective yet flexible recognition. They discriminate strongly against some polysaccharides while remaining relatively promiscuous toward both beta-1,4-linked manno- and cello-oligosaccharides. This feature may reflect preferential, but flexible, targeting toward glucomannans in the plant cell wall. The three-dimensional structure of CBM29-2 and its complexes with cello- and mannohexaose reveal a beta-jelly-roll topology, with an extended binding groove on the concave surface. The orientation of the aromatic residues complements the conformation of the target sugar polymer while accommodation of both manno- and gluco-configured oligo- and polysaccharides is conferred by virtue of the plasticity of the direct interactions from their axial and equatorial 2-hydroxyls, respectively. Such flexible ligand recognition targets the anaerobic fungal complex to a range of different components in the plant cell wall and thus plays a pivotal role in the highly efficient degradation of this composite structure by the microbial eukaryote.

---

Organizational Affiliation: 

Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, York YO10 5YW, United Kingdom.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
NON-CATALYTIC PROTEIN 1	A	153	Piromyces sp. 'equi	Mutation(s): 0  Gene Names: ncp1
Find proteins for Q9C171 (Piromyces equi) Explore Q9C171  Go to UniProtKB:  Q9C171

Oligosaccharides

Help

Entity ID: 2
Molecule	Chains	Chain Length	2D Diagram	Glycosylation
beta-D-glucopyranose-(1-4)-beta-D-glucopyranose-(1-4)-beta-D-glucopyranose-(1-4)-beta-D-glucopyranose-(1-4)-beta-D-glucopyranose-(1-4)-alpha-D-glucopyranose	B	6		N/A

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
EDO	D [auth A], E [auth A], F [auth A], G [auth A], H [auth A], I [auth A], J [auth A], K [auth A]	1,2-ETHANEDIOL C2 H6 O2 LYCAIKOWRPUZTN-UHFFFAOYSA-N
CO	C [auth A]	COBALT (II) ION Co XLJKHNWPARRRJB-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.15 Å
• R-Value Free: 0.156 
• R-Value Work: 0.128 
• R-Value Observed: 0.129 
• Space Group: C 1 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 107.707	α = 90
b = 42.858	β = 105.4
c = 35.555	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
DENZO	data reduction
SCALEPACK	data scaling
AMoRE	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2002-03-19 
• Released Date: 2003-03-20 
Deposition Author(s): Charnock, S.J., Nurizzo, D., Davies, G.J.

Revision History  

• Version 1.0: 2003-03-20
  Type: Initial release
  
• Version 1.1: 2011-05-08
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 2.0: 2020-07-29
  Type: Remediation
  Reason: Carbohydrate remediation
  Changes: Advisory, Atomic model, Data collection, Derived calculations, Other, Structure summary