Biological Assembly 1  

 3D View: Structure | Electron Density

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 21.20 kDa 
• Atom Count: 1414 
• Modelled Residue Count: 178 
• Deposited Residue Count: 191 
• Unique protein chains: 1

2I88

Crystal structure of the Channel-forming Domain of Colicin E1

• DOI: 10.2210/pdb2I88/pdb

• Classification: MEMBRANE PROTEIN
• Organism(s): Escherichia coli
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2006-09-01 Released: 2006-09-26 
• Deposition Author(s): Elkins, P., Bunker, A., Cramer, W.A., Stauffacher, C.V.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• R-Value Free: 0.284 
• R-Value Work: 0.172 
• R-Value Observed: 0.176 

Literature

A mechanism for toxin insertion into membranes is suggested by the crystal structure of the channel-forming domain of colicin E1

Elkins, P., Bunker, A., Cramer, W.A., Stauffacher, C.V.

(1997) Structure 5: 443-458

• PubMed: 9083117 
• DOI: 10.1016/s0969-2126(97)00200-1
• Primary Citation of Related Structures:  
  2I88


• PubMed Abstract: 
  

Channel-forming colicins, including colicin E1, are a sub-family of bacteriocins. The toxic action of colicin E1 is derived from its ability to form a voltage-gated channel, which causes depolarization of the cytoplasmic membrane of sensitive Escherichia coli cells. In this process, the toxin-like colicin E1 molecule must undergo a substantial structural transition from a soluble state, in which it binds the target cell, to a membrane-bound state. Details of the structural changes that accompany this conversion may be directly applicable to other channel-forming toxins, as well as to the mechanism by which proteins insert into or cross membranes.

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Organizational Affiliation: 

Protein Engineering, Department Genentech, Inc. 460 Pt. San Bruno Blvd, South San Francisco, CA 94080, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Colicin-E1	A	191	Escherichia coli	Mutation(s): 0  Gene Names: cea
Find proteins for P02978 (Escherichia coli) Explore P02978  Go to UniProtKB:  P02978

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• R-Value Free: 0.284 
• R-Value Work: 0.172 
• R-Value Observed: 0.176 
• Space Group: I 4

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 87.46	α = 90
b = 87.46	β = 90
c = 59.1	γ = 90

Software Package:

Software Name	Purpose
CNS	refinement
PDB_EXTRACT	data extraction
CrystalClear	data collection
DENZO	data reduction
CCP4	data scaling
CCP4	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2006-09-01 
• Released Date: 2006-09-26 
Deposition Author(s): Elkins, P., Bunker, A., Cramer, W.A., Stauffacher, C.V.

Revision History  

• Version 1.0: 2006-09-26
  Type: Initial release
  
• Version 1.1: 2008-05-01
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2018-01-24
  Changes: Advisory, Structure summary