title: Conversion of rat liver S-adenosyl-L-methionine synthetase from high-Mr form to low-Mr form by LiBr.
abstract: Rat liver S-adenosyl-L-methionine synthetase exists in two forms which are, respectively, a dimer and a tetramer of an Mr 48,500 subunit. The high-molecular-mass form is converted into the low-molecular-mass form by incubation with 1.4 M LiBr. The kinetic properties of the low-molecular-mass form obtained by LiBr treatment are the same as those obtained with the low-molecular-mass S-adenosyl-L-methionine synthetase form purified from rat liver cytosol. These results demonstrate that the differences in specific activity and regulatory properties of the high-molecular-mass and the low-molecular-mass S-adenosyl-L-methionine synthetase forms are due to their different polymeric states.
authors.affiliation: Metabolismo, Nutrición y Hormonas, Fundación Jimenez Diaz, Madrid, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Cabrero
authors.forename: S
authors.initials: S
authors.lastname: Alemany
mesh_terms: D000818:Animals; D001704:Biopolymers; D001965:Bromides / Q000494:pharmacology*; D003600:Cytosol / Q000201:enzymology; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D011756:Diphosphates / Q000494:pharmacology; D008094:Lithium / Q000494:pharmacology*; D018020:Lithium Compounds; D008099:Liver / Q000201:enzymology*; D008716:Methionine Adenosyltransferase / Q000302:isolation & purification / Q000378:metabolism*; D008970:Molecular Weight; D051381:Rats; D014166:Transferases / Q000378:metabolism*
chemical_list: D001704:Biopolymers; D001965:Bromides; D011756:Diphosphates; D018020:Lithium Compounds; C040949:lithium bromide; D008094:Lithium; D014166:Transferases; D008716:Methionine Adenosyltransferase; D004121:Dimethyl Sulfoxide