title: [Complex type of kinetics of fructose-1,6-diphosphate from the rat and rabbit liver].
abstract: Studies on rat and rabbit liver fructose 1.6-bisphosphatase inhibition by AMP showed that with an increase in EDTA concentration the hyperbolic AMP inhibition curve is transformed into a sigmoidal one. At intermediate EDTA concentrations, the kinetic curves have a plateau. The appearance of the intermediate plateau may be due to the superposition of kinetic curves corresponding to two enzyme forms simultaneously present in the assay mixture. One of these forms deprived of endogenous Me2+ (presumably Zn2+) is inhibited by AMP in a cooperative manner, while the other one retains Me2+ which prevents the cooperative response of the enzyme to AMP.
mesh_terms: D000249:Adenosine Monophosphate / Q000494:pharmacology; D000494:Allosteric Regulation; D000818:Animals; D006597:Fructose-Bisphosphatase / Q000037:antagonists & inhibitors; D005635:Fructosediphosphates / Q000378:metabolism*; D006598:Hexosediphosphates / Q000378:metabolism*; D066298:In Vitro Techniques; D007700:Kinetics; D008099:Liver / Q000201:enzymology / Q000378:metabolism*; D011817:Rabbits; D051381:Rats; D011919:Rats, Inbred Strains; D013045:Species Specificity; D015032:Zinc / Q000494:pharmacology
chemical_list: D005635:Fructosediphosphates; D006598:Hexosediphosphates; D000249:Adenosine Monophosphate; D006597:Fructose-Bisphosphatase; D015032:Zinc; C029063:fructose-1,6-diphosphate
vernacular_title: Slozhnyĭ kharakter kinetiki fruktozo-1,6-bifosfata iz pecheni krysy i krolika.