title: Age-linked alterations in fructose-2,6-bisphosphate-induced modulation of rat muscle phosphofructokinase.
abstract: Native muscle phosphofructokinase (PFK: EC 2.7.1.11) isolated from 25- and 100-week-old rats was subjected to in vitro studies on fructose-2,6-bisphosphate-induced alterations in the regulatory roles of other key metabolic modulators of this enzyme. Although fructose 2,6-bisphosphate-mediated reversal of citrate inhibition did not show any age-related difference, synergism with glucose-1,6-bisphosphate effect was found to be slightly increased with the enzyme of 100-week-old rats. In addition, apart from a significant decrease in the extent of fructose-2,6-bisphosphate activation, synergism with AMP activation and reversal of ATP and pyridoxal-5-phosphate inhibitions were observed to be decreased markedly with the enzyme of 100-week-old rats in comparison with that of 25-week-old rats. Such age-dependent alterations in muscle PFK provide evidence for conformational modification in this enzyme as a function of age.
authors.affiliation: Biochemistry and Molecular Biology Laboratory, Banaras Hindu University, Varanasi, India.
authors.forename: S K
authors.initials: SK
authors.lastname: Trigun
authors.forename: S N
authors.initials: SN
authors.lastname: Singh
mesh_terms: D000249:Adenosine Monophosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000494:pharmacology; D000375:Aging / Q000378:metabolism*; D000818:Animals; D002951:Citrates / Q000494:pharmacology; D004789:Enzyme Activation; D005260:Female; D005635:Fructosediphosphates / Q000494:pharmacology*; D006598:Hexosediphosphates / Q000494:pharmacology*; D009132:Muscles / Q000201:enzymology*; D010732:Phosphofructokinase-1 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011732:Pyridoxal Phosphate / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D002951:Citrates; D005635:Fructosediphosphates; D006598:Hexosediphosphates; D000249:Adenosine Monophosphate; D011732:Pyridoxal Phosphate; C027652:fructose 2,6-diphosphate; D000255:Adenosine Triphosphate; D010732:Phosphofructokinase-1