DEVELOPMENTAL PROFILES AND CHARACTERISTICS OF HEMOLYMPH JUVENILE-HORMONE ESTERASE, GENERAL ESTERASE AND JUVENILE-HORMONE BINDING IN THE CRICKET, GRYLLUS-ASSIMILIS

Developmental profiles of serum juvenile hormone esterase (JHE) and ge neral esterase (GE) during the last stadium of the cricket Gryllus ass imilis were highly concordant and exhibited a mid-stadium peak; juveni le hormone binding activity (JHB) increased continuously throughout th e stadium. JHE activities were the highest yet reported in the Orthopt era (peak = 130 nmol/min/ml serum), the enzyme was inhibited strongly by trifluoropropanones (I-50 = 10(-8)-10(-9)) but only weakly by DFP ( 10(-6)) or eserine (10(-4)) and K-m(JH-III) was (16-23 nM). Inhibition studies indicated that the majority of GE activity was due to an enzy me different from JHE. These data provide the background for a study o f the microevolution of the endocrine system in G. assimilis.