Differences in Hydrolysis and Binding of Homologous Juvenile Hormones in Locusta migratoria Hemolymph

Male Locusta hemolymph contains JH-esterase(s) and a JH-carrier protein with high affinity and low capacity that both interact enantioselectively with juvenile hormones. Exposure of racemic JH-I and JH-III results in preferential hydrolysis of the naturally configurated enantiomer of JH-I but the unnaturally configurated enantiomer of JH-III. The JH-carrier protein has a remark­ able specificity for the natural enantiomer of JH-III but discriminates only weakly between enantiomers of JH-I. This observation indicates a protective function of the JH-specific carrier protein for JH-III but not for JH-I. A third major protein, the diglyceride carrier lipoprotein (DGCL), shows no stereoselectivity at all.