title: Isolation and identification of 3-acetylecdysone 2-phosphate, a metabolite of ecdysone, from developing eggs of Schistocerca gregaria.
abstract: A major ecdysteroid conjugate, which accumulates in the eggs of the desert locust, Schistocerca gregaria, during the later stages of embryogenesis, has been isolated by reversed-phase and anion-exchange high-performance liquid chromatography. Hydrolysis of the conjugate with a crude arylsulphatase preparation from Helix pomatia liberates mainly ecdysone 3-acetate. The compound was identified as 3-acetylecdysone 2-phosphate by phosphate analysis of an acid-hydrolysed sample, fast atom bombardment, electron impact and chemical ionization mass spectrometry and 1H and 13Cn.m.r. spectroscopy. The instability of 3-acetylecdysone 2-phosphate on storage results in the formation of ecdysone 2-phosphate, which was identified by physicochemical techniques. 3-Acetylecdysone 2-phosphate and ecdysone 2-phosphate are less susceptible than ecdysone 22-phosphate to hydrolysis in vitro by an enzyme preparation from S. gregaria embryos. The possible role of 3-acetylecdysone 2-phosphate as an inactive end product of ecdysteroid metabolism is discussed.
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004440:Ecdysone / Q000031:analogs & derivatives* / Q000302:isolation & purification; D005260:Female; D006110:Grasshoppers / Q000032:analysis* / Q000196:embryology; D006868:Hydrolysis; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D010063:Ovum / Q000032:analysis
chemical_list: D004440:Ecdysone; C040379:3-acetylecdysone-2-phosphate