title: Analysis of S-methylmethionine and S-adenosylmethionine in plant tissue by a dansylation, dual-isotope method.
abstract: A method is presented for determining the levels of S-methylmethionine (MeMet) and S-adenosylmethionine (AdoMet) in the same plant tissue sample, utilizing readily available equipment. The bottom limit of sensitivity, ca. 100 pmol, can be lowered if required. A trichloracetic acid homogenate of the tissue is supplemented with [carboxyl-14C]MeMet and [carboxyl-14C]AdoMet. After separation of MeMet and AdoMet from each other and from endogenous homoserine on a phosphocellulose column, the two fractions are heat treated at appropriate pH values to liberate [14C]homoserine. Quantitation is via the 3H/14C ratio of [3H]dansyl-[14C]homoserine isolated by thin-layer chromatography. The method is validated with pea cotyledon, corn root, and cauliflower leaf.
mesh_terms: D003619:Dansyl Compounds / Q000032:analysis; D006714:Homoserine / Q000031:analogs & derivatives / Q000032:analysis; D010944:Plants / Q000032:analysis*; D012436:S-Adenosylmethionine / Q000032:analysis*; D014814:Vitamin U / Q000032:analysis*; D014815:Vitamins / Q000032:analysis*
chemical_list: D003619:Dansyl Compounds; D014815:Vitamins; C051050:dansylhomoserine; D014814:Vitamin U; D006714:Homoserine; D012436:S-Adenosylmethionine