A partition assay for the simultaneous determination of insect juvenile hormone esterase and epoxide hydrolase activity

• Published in: Analytical biochemistry Vol. 169; no. 1; pp. 81 - 88
• Main Authors: Share, Marla R., Roe, R.Michael
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 15.02.1988; Elsevier
• Subjects: Acetone - analogs & derivatives; Acetone - pharmacology; Analytical, structural and metabolic biochemistry; Animals; Biological and medical sciences; Carboxylic Ester Hydrolases - analysis; Carboxylic Ester Hydrolases - antagonists & inhibitors; Chromatography, Thin Layer; enzyme assay; Enzymes and enzyme inhibitors; Epoxide Hydrolases - analysis; Fundamental and applied biological sciences. Psychology; Hydrolases; Insecta - enzymology; juvenile hormone; juvenile hormone epoxide hydrolase activity; juvenile hormone esterase activity; liquid scintillation counting; Manduca sexta; Methanol; Octanes; Solubility; Sphingidae; Manduca sexta; enzyme assay; juvenile hormone epoxide hydrolase activity; juvenile hormone; juvenile hormone esterase activity; liquid scintillation counting; Assay; Enzyme; Simultaneous measurement; Enzyme inhibitor; Tritium; Epoxide hydrolase; Biological material; Liquid scintillation; Juvenile hormone esterase
• ISSN: 0003-2697; 1096-0309
• DOI: 10.1016/0003-2697(88)90257-6

A partition assay was developed to measure insect juvenile hormone (JH) I and III metabolism in biological samples containing both JH esterase and JH epoxide hydrolase activity. The assay utilizes commercially available radiochain 3H-labeled JH as substrate and the selective JH esterase inhibitor 3-octylthio-1,1,1-trifluoro-2-propanone. JH partitions into an isooctane phase and the metabolites JH acid, JH diol, and JH diol-acid into aqueous methanol after incubation of JH substrate with inhibited and uninhibited sample. The assay provides a time-and cost-efficient alternative to the currently available thin-layer chromatography method for the measurement of JH esterase and epoxide hydrolase activity.