Biological Assembly 1  

 3D View: Structure | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Homo 3-mer - A3 

Biological assembly 1 generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 6.34 kDa 
• Atom Count: 449 
• Residue Count: 63 
• Unique protein chains: 1

1AMT

Crystal structure of alamethicin at 1.5 angstrom resolution

• DOI: 10.2210/pdb1AMT/pdb

• Classification: ANTIBIOTIC
• Organism(s): Trichoderma viride
• Mutation(s): No 


• Deposited: 1987-12-08 Released: 1988-10-09 
• Deposition Author(s): Fox, R.O., Richards, F.M.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.50 Å
• R-Value Observed: 0.155 

Literature

A Voltage-Gated Ion Channel Model Inferred from the Crystal Structure of Alamethicin at 1.5-A Resolution.

Fox Jr, R.O., Richards, F.M.

(1982) Nature 300: 325

• PubMed: 6292726 
• DOI: 10.1038/300325a0
• Primary Citation of Related Structures:  
  1AMT


• PubMed Abstract: 
  

The crystal structure of alamethicin in nonaqueous solvent has been determined, and refined at 1.5-A resolution. The molecular conformation of the three crystallographically independent molecules is largely alpha-helical with a bend in the helix axis at an internal proline residue. The helix structure is highly amphipathic as most of the solvent-accessible polar atoms lie on a narrow strip of surface parallel to the helix axis. Molecular models for the voltage-gated ion channel, with n-fold symmetry and based on the molecular conformations observed in the crystal, are characterized by strong surface complementarity, a hydrophilic interior and a hydrophobic exterior. The channel structures are stabilized by a hydrated annulus of hydrogen-bonded glutamine residues which produce the greatest restriction in the channel diameter.

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Related Citations: 

• The Crystal Structure of Alamethicin at 1.5 Angstroms Resolution
  Fox, R.O.
  () Thesis, Yale --: --

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Organizational Affiliation: 

Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA; Department of Tumor Cell Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA; Howard Hughes Medical Institute, St. Jude Children's Research Hospital, Memphis, TN 38105, USA. Electronic address: [e-mail].

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
ALAMETHICIN F30	A, B, C	21	Trichoderma viride	Mutation(s): 0

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
CCN	A, B	ACETONITRILE C2 H3 N WEVYAHXRMPXWCK-UHFFFAOYSA-N
MOH	A, B, C	METHANOL C H4 O OKKJLVBELUTLKV-UHFFFAOYSA-N

Modified Residues  2 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
AIB	A,B,C	L-PEPTIDE LINKING	C4 H9 N O2		ALA
PHL	A,B,C	L-PEPTIDE LINKING	C9 H13 N O		PHE

Biologically Interesting Molecules (External Reference) 1 Unique

Entity ID: 1
ID	Chains	Name	Type/Class	2D Diagram	3D Interactions
PRD_000163	A, B, C	Alamethicin	Peptaibol /  Antibiotic		--

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.50 Å
• R-Value Observed: 0.155 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 33.33	α = 90
b = 29.62	β = 120.4
c = 23.2	γ = 90

Software Package:

Software Name	Purpose
PROLSQ	refinement

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1987-12-08 
• Released Date: 1988-10-09 
Deposition Author(s): Fox, R.O., Richards, F.M.

Revision History 

• Version 1.0: 1988-10-09
  Type: Initial release
  
• Version 1.1: 2011-06-14
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2011-07-27
  Changes: Atomic model, Database references, Derived calculations, Non-polymer description, Structure summary
• Version 1.4: 2012-12-12
  Changes: Other
• Version 1.5: 2017-11-01
  Changes: Derived calculations, Other