Characterization of the juvenile hormone epoxide hydrolase (JHEH) and juvenile hormone diol phosphotransferase (JHDPT) from Manduca sexta Malpighian tubules

✍ Scribed by Michael L. Grieneisen; Travis D. Kieckbusch; Amy Mok; György Dorman; Bachir Latli; Glenn D. Prestwich; David A. Schooley

• Book ID: 102749184
• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 937 KB
• Volume: 30
• Category: Article
• ISSN: 0739-4462
• DOI: 10.1002/arch.940300213

✦ Synopsis

Juvenile hormone epoxide hydrolase (JHEH) and juvenile hormone diol phosphotransferase (JHDPT) were characterized from the Malpighian tubules of day 1 fifth instar Manduca sexta. An improved RP-HPLC assay is described for the major metabolites of (lOR,lIS) juvenile hormone I: diol, acid, aciddiol, and diol-phosphate. JHEH is strictly associated with membrane fractions, while JHDPT is cytosolic. JHEH may be solubilized in active form by the nonionic detergents Thesit or MEGA-8. Separation of Malpighian tubule cytosol proteins using preparative isoelectric focusing yields two zones which contain JHDPT activity, at pi 4.8-5.1 and 6.8-8.2. The partially purified JHDPT from either zone requires both ATP and Mg2+ for activity, so this enzyme may be formally called either ATP:juveni/e hormone diol phosphotransferase or juvenile hormone diol kinase (EC 2.1.7.3). Metabolites more polar than JH I aciddiol and JH I diol-phosphate are generated in vivo from either [3H]JH I or 13H]JH I diol.