title: Possibility of mutation prediction of influenza hemagglutinin by combination of hemadsorption experiment and quantum chemical calculation for antibody binding.
abstract: We have performed a quantum-chemical MP2/6-31G* calculation for the hemagglutinin (HA) antigen-antibody system of the H3N2 influenza virus with the fragment molecular orbital method, which provides one of the world's largest ab initio electron-correlated calculations for biomolecular systems. On the basis of the calculated interfragment interaction energies (IFIEs) representing the molecular interactions between the amino acid residues in the antigen-antibody complex, we have identified those residues in the antigenic region E of HA protein that are significantly recognized by the Fab fragment of antibody with strongly attractive interactions. Combining these IFIE results with those of hemadsorption experiments by which the mutation-prohibited sites are specified has enabled us to explain most of the historical mutation data (five of six residues), which would thus provide a promising method for predicting the HA residues that have a high probability of forthcoming mutation.
authors.affiliation: Graduate School of Human Development and Environment, Kobe University, 3-11 Tsurukabuto, Nada-ku, Kobe 657-8501, Japan.
authors.forename: Kazutomo
authors.initials: K
authors.lastname: Takematsu
authors.forename: Kaori
authors.initials: K
authors.lastname: Fukuzawa
authors.forename: Katsumi
authors.initials: K
authors.lastname: Omagari
authors.forename: Setsuko
authors.initials: S
authors.lastname: Nakajima
authors.forename: Katsuhisa
authors.initials: K
authors.lastname: Nakajima
authors.forename: Yuji
authors.initials: Y
authors.lastname: Mochizuki
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Nakano
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Watanabe
authors.forename: Shigenori
authors.initials: S
authors.lastname: Tanaka