Isoelectric focusing in agarose: a highly discriminatory method for the detection of enzyme heterogeneity.

A comparison was made of the effectiveness of starch gel electrophoresis and isoelectric focusing in agarose for the separation of isoenzymes. Lactate dehydrogenase (LDH) of Theileria parva and glucose phosphate isomerase (GPI) of various cestodes were examined by the two techniques. Isoelectric focusing proved to be highly discriminatory, clearly distinguishing cestode orders and Taenia spp. which were closely similar by starch gel electrophoresis, and separating seven bands of Theileria-specific LDH activity which were not separable from normal bovine control bands on starch gels. The routine use of isoelectric focusing in agarose is therefore recommended for isoenzyme analysis.