In particular , amino acid substitutions that change the electric charge of the enzyme ( such as replacing aspartic acid with glutamic acid ) are simple to identify by gel electrophoresis .
This forms the basis for the use of isozymes as molecular markers .
In particular , amino acid substitutions that change the electric charge of the enzyme ( such as replacing aspartic acid with glutamic acid ) are simple to identify by gel electrophoresis , and this forms the basis for the use of isozymes as molecular markers .