title: Methylation of estradiol-17 beta by a partially purified preparation of bovine pineal hydroxy-indole-O-methyltransferase.
abstract: A partially purified preparation of hydroxy-indole-O-methyltransferase (HIOMT) from bovine pineal was shown to O-methylate estradiol-17beta (E2). The HIOMT preparation was incubated with E2 and [3H]-S-adenosylmethionine (SAM). The [3H]-3 methyl-ether or estradiol [MeO-E2] produced was identified by thin layer chromatography (TLC) and crystallization to constant 3H/14C ratio in the presence of [14C]-MeO-E2 and unlabeled MeO-E2 standards. The kinetics of the enzyme reaction for melatonin formation from N-acetyl-serotonin (NAS) and for MeO-E2 were compared.
mesh_terms: D000121:Acetylserotonin O-Methyltransferase / Q000378:metabolism*; D000818:Animals; D002417:Cattle; D004958:Estradiol / Q000378:metabolism*; D007700:Kinetics; D008745:Methylation; D008780:Methyltransferases / Q000378:metabolism*; D010870:Pineal Gland / Q000201:enzymology*; D013379:Substrate Specificity
chemical_list: D004958:Estradiol; D008780:Methyltransferases; D000121:Acetylserotonin O-Methyltransferase