title: Biosynthetic studies on the tropane alkaloid hyoscyamine in Datura stramonium; hyoscyamine is stable to in vivo oxidation and is not derived from littorine via a vicinal interchange process.
abstract: The conversion of littorine to hyoscyamine has been investigated by feeding deuterium labelled (RS)-[2-(2)H]-, [3, 3-(2)H(2)]-, [2, 3, 3-(2)H(3)]- phenyllactic acids to transformed root cultures of Datura stramonium. Isolation and GC-MS analyses of the isotope incorporation into the resultant hyoscyamine does not support the involvement of a vicinal interchange process operating during the isomerisation of littorine to hyoscyamine. Additionally a metabolism study with [1'-13C, 3', 3'-(2)H(2)]-hyoscyamine has established that the alkaloid is metabolically stable at C-3' with no evidence for a reversible in vivo oxidation process to the corresponding aldehyde. The data do not support an S-adenosy-L-methionine (SAM 5)/co-enzyme-B(12) mediated process for the isomerisation of littorine to hyoscyamine.
mesh_terms: D001285:Atropine / Q000096:biosynthesis* / Q000737:chemistry / Q000378:metabolism*; D001286:Atropine Derivatives / Q000737:chemistry / Q000378:metabolism*; D002247:Carbon Isotopes; D002457:Cell Extracts; D002478:Cells, Cultured; D003038:Cobamides / Q000378:metabolism; D013286:Datura stramonium / Q000166:cytology / Q000378:metabolism*; D003903:Deuterium; D008401:Gas Chromatography-Mass Spectrometry; D007536:Isomerism; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010084:Oxidation-Reduction; D018517:Plant Roots / Q000166:cytology / Q000378:metabolism; D012436:S-Adenosylmethionine / Q000378:metabolism
chemical_list: D001286:Atropine Derivatives; D002247:Carbon Isotopes; D002457:Cell Extracts; D003038:Cobamides; C063158:littorine; D001285:Atropine; D012436:S-Adenosylmethionine; D003903:Deuterium; C000913:cobamamide