title: Charge-state and charge-continuum models in electrophoresis and isoelectric focusing of genetic variants.
abstract: A model which combines the charge-state and charge-continuum models is considered in terms of the pH at which the electrophoretic analysis is made. "Unit" charge changes are obtained when the mutated charged group is at least 2 pH units apart from the pI of the protein. "Fractional" charge changes are found when the differences between the pK of the mutated charged group and the pI of the protein becomes progressively smaller, or when the pK of the ionizable group lies on the "wrong" side of the protein pI. It is possible to measure the pK of a modified group in a protein when the delta pI per protonic unit in a given family of proteins (e.g., haemoglobin mutants) is less than unity.
mesh_terms: D000596:Amino Acids / Q000032:analysis / Q000235:genetics*; D004563:Electrochemistry; D004586:Electrophoresis; D014644:Genetic Variation; D006454:Hemoglobins / Q000032:analysis; D007525:Isoelectric Focusing; D008957:Models, Genetic
chemical_list: D000596:Amino Acids; D006454:Hemoglobins