title: Influence of mutations at the proximal histidine position on the Fe-O2 bond in hemoglobin from density functional theory.
abstract: Four mutated hemoglobin (Hb) variants and wild type hemoglobin as a reference have been investigated using density functional theory methods focusing on oxygen binding. Dispersion-corrected B3LYP functional is used and found to provide reliable oxygen binding energies. It also correctly reproduces the spin distribution of both bound and free heme groups as well as provides correct geometries at their close vicinity. Mutations in hemoglobin are not only an intrigued biological problem and it is also highly important to understand their effects from a clinical point of view. This study clearly shows how even small structural differences close to the heme group can have a significant effect in reducing the oxygen binding of mutated hemoglobins and consequently affecting the health condition of the patient suffering from the mutations. All of the studied mutated Hb variants did exhibit much weaker binding of molecular oxygen compared to the wild type of hemoglobin.
authors.affiliation: Division of Physical Chemistry, Arrhenius Laboratory, Department of Materials and Environmental Chemistry, Stockholm University, S 106 91 Stockholm, Sweden.
authors.forename: Guido
authors.initials: G
authors.lastname: Todde
authors.affiliation: Division of Structural Chemistry, Arrhenius Laboratory, Department of Materials and Environmental Chemistry, Stockholm University, S 106 91 Stockholm, Sweden.
authors.forename: Sven
authors.initials: S
authors.lastname: Hovmöller
authors.affiliation: Division of Physical Chemistry, Arrhenius Laboratory, Department of Materials and Environmental Chemistry, Stockholm University, S 106 91 Stockholm, Sweden.
authors.forename: Aatto
authors.initials: A
authors.lastname: Laaksonen
mesh_terms: D005290:Ferric Compounds / Q000737:chemistry*; D006454:Hemoglobins / Q000737:chemistry*; D006639:Histidine / Q000737:chemistry*; D008958:Models, Molecular; D009154:Mutation
chemical_list: D005290:Ferric Compounds; D006454:Hemoglobins; C000499:ferric oxide; D006639:Histidine