부산대학교 도서관

A number of α-amino and α-keto acids have been shown to inhibit saccharopine dehydrogenase [∊-N-(L-glutaryl-2)-L-lysine : NAD) oxidoreductase (lysine forming)] in the direction of saccharopine formation. Among amino acids those having aliphatic side chains of 5 and 6 carbon atoms were best inhibitors. Dicarboxylic amino acids, aspartate, glutamate, and 2-ammoadipate were not inhibitory, Kinetic analyses have shown that the inhibition by these compounds was competitive with respect to lysine and uncompetitive with respect to NADH and 2-oxoglutarate, and are consistent with the mechanism that the ammo acid inhibitors combine with the lysine-binding site of the enzyme. α-Keto acids, on the other hand, produced non-competitive inhibition with any of the three reactants as the variable. Substrate inhibition by 2-oxoglutarate and the non-linear nature of inhibition suggest that these compounds also bind to the enzyme at site(s) other than the active site. [ABSTRACT FROM AUTHOR]