title: Roles of the histidine and tryptophan side chains in the M2 proton channel from influenza A virus.
abstract: The M2 protein form influenza A virus forms a tetrameric ion channel, which enables proton passage across biological membranes when the N-terminal side is acidified. Among the amino acid residues in the transmembrane domain of the M2 protein, His37 and Trp41 are essential for the pH-regulated proton conductance. Current knowledge about the structures and interactions of His37 and Trp41 suggests a model for the M2 ion channel, in which the channel is closed by a network of His37 hydrogen bonds at neutral pH and is opened by a His37-Trp41 cation-pi interaction at acidic pH.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Tohoku University, Aobayama, Sendai 980-8578, Japan. takeuchi@mail.cc.tohoku.ac.jp
authors.forename: Hideo
authors.initials: H
authors.lastname: Takeuchi
authors.forename: Atsushi
authors.initials: A
authors.lastname: Okada
authors.forename: Takashi
authors.initials: T
authors.lastname: Miura
mesh_terms: D002412:Cations; D006639:Histidine / Q000737:chemistry*; D006860:Hydrogen Bonding; D006863:Hydrogen-Ion Concentration; D007477:Ions; D008958:Models, Molecular; D011487:Protein Conformation; D011522:Protons; D013059:Spectrum Analysis, Raman; D014364:Tryptophan / Q000737:chemistry*; D014466:Ultraviolet Rays; D014763:Viral Matrix Proteins / Q000737:chemistry*; D000086082:Viroporin Proteins
chemical_list: D002412:Cations; D006639:Histidine; D007477:Ions; D011522:Protons; D014364:Tryptophan; D014763:Viral Matrix Proteins; C031540:M-protein, influenza virus; C488937:M2 protein, Influenza A virus; D000086082:Viroporin Proteins