[Interaction of muscle glycogen phosphorylase b with nicotinic acid, nicotinamide, N-nicotinyl-gamma-aminobutyric acid and nicotinamide coenzymes].
The inhibitory action of nicotinic acid, nicotinamide, N-nicotinoyl-gamma-aminobutyric acid, NAD, NADH, NADP, and NADPH on the rabbit skeletal muscle glycogen phosphorylase b has been studied. The inhibition is reversible and positively cooperative (the value of Hill coefficients were determined for the following compounds: nicotinic acid (28 mM; 1.4), nicotinamide (4.4 mM; 1.2), N-nicotinoyl-gamma-aminobutyric acid (9.5 mM; 1.4), NAD (4.4 mM; 1.2), NADH (0.93 mM; 1.2). NADH-binding site of glycogen phosphorylase b subunit was characterized by the sedimentation velocity method. Microscopic dissociation constant was found to be 86 +/- 9 microM (pH 6.8; 20 degrees C). AMP-induced association of glycogen phosphorylase b is hindered by NADH.
D000818:Animals; D066298:In Vitro Techniques; D007700:Kinetics; D009132:Muscles / Q000201:enzymology; D009243:NAD / Q000378:metabolism / Q000494:pharmacology*; D009249:NADP / Q000378:metabolism / Q000494:pharmacology*; D009536:Niacinamide / Q000378:metabolism / Q000494:pharmacology*; D009539:Nicotinic Acids / Q000378:metabolism / Q000494:pharmacology*; D010763:Phosphorylase b / Q000037:antagonists & inhibitors* / Q000378:metabolism; D006005:Phosphorylases / Q000037:antagonists & inhibitors*; D011817:Rabbits; D013379:Substrate Specificity; D005680:gamma-Aminobutyric Acid / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology
D009539:Nicotinic Acids; D009243:NAD; D009536:Niacinamide; D009249:NADP; D005680:gamma-Aminobutyric Acid; D010763:Phosphorylase b; D006005:Phosphorylases
Vzaimodeĭstvie myshechnoĭ glikogenfosforilazy b s nikotinovoĭ kislotoĭ, nikotinamidom, N-nikotinoil-gamma-aminomaslianoĭ kislotoĭ i nikotinamidnymi kofermentami.