A NOVEL-APPROACH FOR THE IDENTIFICATION OF ISOZYMES USING INHIBITORS

Carboxylesterase isozymes of a termite and a fungus, have been identif ied by exploiting their differential sensitivity towards organophospha te inhibitors. The inhibition curves obtained by plotting pI(negative logarithm of inhibitor concentration) versus per cent inhibition are u sed to distinguish the isozymes. The termite and its associated fungus possess 2 and 4 isozymes respectively. Each of the purified isozyme g ave a single sigmoidal inhibition curve with its characteristic I-50 v alue. The pattern of the inhibition curve of the crude extract is foun d to mimic that of the mixture of the purified isozymes in both termit e and fungus. This method provides not only identification of isozymes but also serves as a criterion of homogeneity.