Open AccessHormonal effects on structure and catalytic properties of fructose 1,6-bisphosphatase.
Author(s) -
S. Pontremoli,
Antonio De Flora,
Franca Salamino,
Edon Melloni,
B.L. Horecker
Publication year - 1975
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.72.8.2969
Subject(s) - fructose 1,6 bisphosphatase , allosteric regulation , gluconeogenesis , fructose , protein subunit , biochemistry , chemistry , glycogenolysis , proteases , enzyme , histidine , medicine , endocrinology , biology , glycogen , gene
Gluconeogenic conditions, such as administration of triamcinolone or alloxan diabetes, cause the following changes in the molecular structure and properties of rabbit liver fructose 1,6-bisphosphatase (D-fructose-1,6-bisphosphate 1-phosphohydrolase, EC 3.1.3.11): (1) the appearance of traces (about 10%) of a lighter subunit; (2) loss of tryptophan from all of the subunits, including those that show no apparent change in molecular weight; (3) increase in requirement for the positive allosteric effector, histidine; (4) increase in amount of enzyme, but not its specific activity. These changes are identical to those induced by cold or fasting, and are related to increased activities of lysosomal proteases. The results suggest that lysosomes may act as mediators of gluconeogenic stimuli.