4QKL

Influenza A M2 wild type TM domain at high pH in the lipidic cubic phase under room temperature diffraction conditions


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.71 Å
  • R-Value Free: 0.198 
  • R-Value Work: 0.166 
  • R-Value Observed: 0.169 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

High-resolution structures of the M2 channel from influenza A virus reveal dynamic pathways for proton stabilization and transduction.

Thomaston, J.L.Alfonso-Prieto, M.Woldeyes, R.A.Fraser, J.S.Klein, M.L.Fiorin, G.DeGrado, W.F.

(2015) Proc Natl Acad Sci U S A 112: 14260-14265

  • DOI: 10.1073/pnas.1518493112
  • Primary Citation of Related Structures:  
    4QK7, 4QKC, 4QKL, 4QKM

  • PubMed Abstract: 
  • The matrix 2 (M2) protein from influenza A virus is a proton channel that uses His37 as a selectivity filter. Here we report high-resolution (1.10 Å) cryogenic crystallographic structures of the transmembrane domain of M2 at low and high pH. These structures reveal that waters within the pore form hydrogen-bonded networks or "water wires" spanning 17 Å from the channel entrance to His37 ...

    The matrix 2 (M2) protein from influenza A virus is a proton channel that uses His37 as a selectivity filter. Here we report high-resolution (1.10 Å) cryogenic crystallographic structures of the transmembrane domain of M2 at low and high pH. These structures reveal that waters within the pore form hydrogen-bonded networks or "water wires" spanning 17 Å from the channel entrance to His37. Pore-lining carbonyl groups are well situated to stabilize hydronium via second-shell interactions involving bridging water molecules. In addition, room temperature crystallographic structures indicate that water becomes increasingly fluid with increasing temperature and decreasing pH, despite the higher electrostatic field. Complementary molecular dynamics simulations reveal a collective switch of hydrogen bond orientations that can contribute to the directionality of proton flux as His37 is dynamically protonated and deprotonated in the conduction cycle.


    Organizational Affiliation

    Department of Pharmaceutical Chemistry, University of San Francisco, San Francisco, CA 94158; william.degrado@ucsf.edu giacomo.fiorin@temple.edu.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
influenza M2 monomer, TM domain (22-46)A27Influenza A virus (A/udorn/1972(H3N2))Mutation(s): 2 
UniProt
Find proteins for P0DOF5 (Influenza A virus (strain A/Udorn/307/1972 H3N2))
Explore P0DOF5 
Go to UniProtKB:  P0DOF5
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
EDO
Query on EDO

Download Ideal Coordinates CCD File 
E [auth A]1,2-ETHANEDIOL
C2 H6 O2
LYCAIKOWRPUZTN-UHFFFAOYSA-N
 Ligand Interaction
CA
Query on CA

Download Ideal Coordinates CCD File 
C [auth A], D [auth A]CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
CL
Query on CL

Download Ideal Coordinates CCD File 
B [auth A]CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.71 Å
  • R-Value Free: 0.198 
  • R-Value Work: 0.166 
  • R-Value Observed: 0.169 
  • Space Group: I 4
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 29.6α = 90
b = 29.6β = 90
c = 68.14γ = 90
Software Package:
Software NamePurpose
Blu-Icedata collection
PHASERphasing
PHENIXrefinement
MOSFLMdata reduction
Aimlessdata scaling

Structure Validation

View Full Validation Report




Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2015-11-11
    Type: Initial release
  • Version 1.1: 2015-12-16
    Changes: Database references