Macromolecule Content

• Total Structure Weight: 41.48 kDa 
• Atom Count: 1924 
• Residue Count: 244 
• Unique protein chains: 1

2KJ1

cytoplasmic domain structure of BM2 proton channel from influenza B virus

• DOI: 10.2210/pdb2KJ1/pdb

• Classification: TRANSPORT PROTEIN
• Organism(s): Influenza B virus
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2009-05-13 Released: 2009-11-10 
• Deposition Author(s): Wang, J., Pielak, R., McClintock, M., Chou, J.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 100 
• Conformers Submitted: 15 
• Selection Criteria: structures with the lowest energy 

Literature

Solution structure and functional analysis of the influenza B proton channel.

Wang, J., Pielak, R.M., McClintock, M.A., Chou, J.J.

(2009) Nat Struct Mol Biol 16: 1267-1271

• PubMed: 19898475 
• DOI: 10.1038/nsmb.1707
• Primary Citation of Related Structures:  
  2KJ1, 2KIX


• PubMed Abstract: 
  

Influenza B virus contains an integral membrane protein, BM2, that oligomerizes in the viral membrane to form a pH-activated proton channel. Here we report the solution structures of both the membrane-embedded channel domain and the cytoplasmic domain of BM2. The channel domain assumes a left-handed coiled-coil tetramer formation with a helical packing angle of -37 degrees to form a polar pore in the membrane for conducting ions. Mutagenesis and proton flux experiments identified residues involved in proton relay and suggest a mechanism of proton conductance. The cytoplasmic domain of BM2 also forms a coiled-coil tetramer. It has a bipolar charge distribution, in which a negatively charged region interacts specifically with the M1 matrix protein that is involved in packaging the genome in the virion. This interaction suggests BM2 also recruits matrix proteins to the cell surface during virus budding, making BM2 an unusual membrane protein with the dual roles of conducting ions and recruiting proteins to the membrane.

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Organizational Affiliation: 

Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
BM2 protein	A, B, C, D	89	Influenza B virus	Mutation(s): 0  Gene Names: BM2
Membrane protein Mpstruc	Group:  TRANSMEMBRANE PROTEINS: ALPHA-HELICAL		Sub Group:  Channels: Other Ion Channels	Protein:  M2 proton channel (BM2)
Find proteins for Q9WD75 (Influenza B virus) Explore Q9WD75  Go to UniProtKB:  Q9WD75

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 100 
• Conformers Submitted: 15 
• Selection Criteria: structures with the lowest energy 
• OLDERADO: 2KJ1 Olderado

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2009-05-13 
• Released Date: 2009-11-10 
Deposition Author(s): Wang, J., Pielak, R., McClintock, M., Chou, J.

Revision History 

• Version 1.0: 2009-11-10
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Version format compliance