Possible Interaction: Adenosine Triphosphate and Methionine

“We report that methionine substitution, but not leucine substitution, results in increased open state stability and hence significantly reduced ATP sensitivity and a marked increase of channel activity in the intact cell irrespective of the identity of the coassembled SUR subunit.”

“ ATP contents were reduced by MET analogs only in HCY+ medium, suggesting complementary effects of MET analogs and HCY.”

“In Hcy synthesis, methionine is activated by ATP to form S-adenosylmethionine (SAM).”

“However, at a high concentration, above 4 10−5 M (about 82 µg/ml), the ATP enzymatic activity was inhibited, affecting the function of hRBCs.”

“AF at 10−5 M significantly increases the ATP (33%;P < 0.03).”

“Initial velocity studies of substrate dependence and product inhibition indicate a steady state mechanism that is ordered Bi Ter with ATP adding before L-methionine and S-adenosylmethionine as the first product released.”

“The chronic administration of Met and/or MetO also promotes alteration in the hydrolysis of ATP and ADP, as indicated by the increased activity of ectonucleotidases.”

“ ATP and AMP hydrolysis was decreased by Met (1 and 2 mM), Met-SO and Met (1 and 2 mM) + Met-SO treatment, while ADP hydrolysis was enhanced by Met-SO and Met (1 and 2 mM) + Met-SO (P < 0.05).”

“In a concentration of 10—5 M , they inhibited active Ca2+ transport by 57±6, 75±8, 80±8, and 85±9% and ATP hydrolysis by 0, 40±4, 48±5, and 38±4%, respectively.”

“Also, ATP and ADP (but not AMP) catabolism decreased significantly at both Met concentrations tested.”