S-adenosyl-L-methionine modulates Na+ + K+-ATPase activity in rat colonic basolateral membranes.

摘要: Rat colonic basolateral membranes were incubated with S-adenosyl-L-[methyl-3H]methionine (0.3 mM) at 37 degrees C for 2 h pH 9.0. This resulted in an increase the specific activity of Na+ + K+-ATPase by 60%. Kinetic parameter analysis revealed a 2-fold Vmax. this enzymatic activity, whereas Km ATP was unchanged. The methylation inhibitor S-adenosyl-L-homocysteine (2 significantly reduced these S-adenosyl-L-methionine-stimulated increases and K+-ATPase. S-Adenosyl-L-methionine treatment also found to fluidity preparations, as assessed steady-state fluorescence polarization techniques using fluorophore 1,6-diphenyl-1,3,5-hexatriene; again markedly S-adenosyl-L-methionine-induced fluidity. While transmethylation reactions involving phospholipids, non-polar lipids proteins all exist rat membranes, based on number observations, results present studies suggest that membrane but not or proteins, influenced which, turn, modified membranes.