Electrostatic energy calculation on the pH-induced conformational change of influenza virus hemagglutinin.
The pH-induced conformational change of influenza virus hemagglutinin (HA) has been investigated by calculating the change of electrostatic energy of the fragment of HA2 upon pH change. The average charge and electrostatic free energy are calculated as a function of pH for the fusion peptide (residues 1-20 of HA2) and the polypeptide of residues 54-77 of HA2 by using the finite difference Poisson-Boltzmann method. It is found that as pH decreases from 8 to 5, the electrostatic free energy of the fusogenic state is lowered by approximately 2 kcal/mol and the fusogenic state is less ionized compared to that of the native state for both polypeptides. For the fusion peptide at the fusogenic state, most of ionizable residues are neutral at acidic pH except Glu-11. For the polypeptide of residues 54-77 at the fusogenic state, most of residues except Glu-74 and His-64 are fully charged between pH 5 and pH 8.
Choi
Ho Sup
HS
Hyperstructured Organic Materials Research Center, School of Material Science and Engineering, Seoul National University, Seoul, Korea.
Huh
June
J
Jo
Won Ho
WH
D003198:Computer Simulation; D004735:Energy Transfer; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000737:chemistry* / Q000648:ultrastructure*; D006863:Hydrogen-Ion Concentration; D008956:Models, Chemical; D008958:Models, Molecular; D011487:Protein Conformation; D055672:Static Electricity; D013816:Thermodynamics
D019267:Hemagglutinin Glycoproteins, Influenza Virus