Some properties of the haemolymph juvenile hormone esterases in Galleria mellonella larvae and Tenebrio molitor pupae

Abstract

The apparent molecular weight, the K m , and the sensitivity to different organophosphates of the haemolymph juvenile hormone esterase (JHE) in the larvae of Galleria mellonella was determined. The apparent molecular weight, determined by gel filtration methods, was estimated to be 60,000. The apparent K m of the enzyme was 1.79 μM. The enzyme was insensitive to diisopropylphosphofluoridate (DFP) but was sensitive to paraoxon and 0-ethyl-S-phenylphosphoramidothiolate (EPPAT). The sensitivity of JHE in pupae of Tenebrio molitor to organophosphates was also determined. It was found to be insensitive to DFP and EPPAT.