PURIFICATION OF (-DELTA-CADINENE SYNTHASE, A SESQUITERPENE CYCLASE FROM BACTERIA-INOCULATED COTTON FOLIAR TISSUE())

A sesquiterpene cyclase whose activity is induced in a glandless, bact erial blight-resistant line of cotton (Gossypium hirsutum L.) catalyse s the conversion of (E, E)-farnesyl diphosphate to (+)-delta-cadinene. This enzyme was purified by a combination of salt-induced phase separ ation, hydroxylapatite fractionation, hydrophobic interaction and stro ng anion-exchange chromatography, and denaturing polyacrylamide gel el ectrophoresis, followed by renaturation with Tween 80. The purified en zyme has a molecular weight of 64-65 kDa, and exhibited a single silve r-staining band following electrophoresis in analytical denaturing pol yacrylamide gels. Amino acid sequences of three tryptic peptides from the enzyme have been determined and are similar to known sequences in other terpene cyclases from plants.