[Comparative study of the structural characteristics of aldolase in rabbit muscles in normal states and in alloxan diabetes].

It is shown that the activity of aldolase synthesized in rabbit muscles under diabetes is higher than that at normal state. This fact is probably a result of some structural alterations in NAD-binding site with Trp-291 and -311 in it which overlaps a considerable part of C-terminal region of the protein. The hydrophobic part of the enzyme containing Trp-147 under diabetes seems to remain unaltered.

[Effect of NADH on the catalytic function and reactivity of thiols from rabbit muscle aldolase].

NADH has a corresponding binding site in aldolase, and can activate the reaction of the aldole cleavage of the substrate (fructose-1,6-bisphosphate). Unlike the considerable protection by the substrate, the similar effect of NADH on the sulphydryl enzyme groups is less pronounced, and may be attributed to single cysteine residue. The functionally related and spatially separated binding sites for NADH and substrate are suggested.