sentences:  For example, the biotin-streptavidin interaction can be broken by incubating the complex in water at 70 °C, without damaging either molecule.An example of change in local concentration causing dissociation can be found in the Bohr effect, which describes the dissociation of ligands from hemoglobin in the lung versus peripheral tissues.Some protein–protein interactions result in covalent bonding, and some pharmaceuticals are irreversible antagonists that may or may not be covalently bound.