ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 20, Number 5
JKCSEZ 20(5)
October 20, 1976 

A series of N1-alkylnicotinamide chlorides, N1-methyl-to N1-dodecylnicotinamides inclusive were studied with rabbit muscle L-α-glycerophosphate dehydrogenase to investigate the possibility of reversible and irreversible inactivation of the pyridine-linked dehydrogenases by the coenzyme-competitive inhibitor derivatives. The inhibition of the enzyme by N1-alkylnicotinamide chlorides was demonstrated to be reversible at the dilute concentration of the inhibitors but this reversible inhibition was found to be followed by an irreversible time-dependent inactivation measuable at high concentrations of the inhibitors. The properties of this time-dependent inactivation were discussed on the basis of the denaturation of the enzyme by the binding of small micelle-like structures formed at higher concentrations of the inhibitors.