Effect of nano metal oxides on heme molecule: molecular and biomolecular approaches

Abstract

Interaction of components of living cells with various nanomaterials in the gas phase has been one of extensive concern since they become intensively utilized in various life aspects. This work is carried out to investigate the interaction between heme molecule, as the main component of hemoglobin, with several familiar and non-familiar divalent structures such as O2, CO2, CO, MgO, CoO, NiO, CuO and ZnO. Geometry optimization processes as well as QSAR descriptors are conducted using semiemprical quantum mechanical calculations at PM6 level. Results illustrate that adsorbing O2 and CO on heme lowers their TDM helping heme in performing its transportation function and not interacting with other species. On the other hand, when CoO and ZnO interacting with heme the TDM of the resultant structures increase greatly reflecting high reactivity which may interact with other species more than performing its function. Therefore, interacting species other than O2 may disturb the transportation function of heme structure. QSAR data of IP regarding interaction of O2 with heme ensure the TDM result that reflects lowering its activity. IP of H-CO adsorbed is the lowest indicating high reactivity while those of H-O2, H-CO2, H-MgO and H-NiO in the complex form are the highest values indicating that it is difficult to form a complex structure with them. Therefore, heme interactions with structures rather than O2 and CO2 affects negatively its function as gas transporter.