Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.3.1 (alkaline phosphatase)
 47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

6-Phosphofructo-2-kinase (PFK-2) was analyzed in four organs of the anoxia-tolerant marine gastropod mollusk Busycon canaliculatum. Whelk PFK-2 resembled the nonhepatic enzyme from mammals with highest activity occurring in gill (22 pmol.min-1.g-1). Hepatopancreas PFK-2 was purified over 8,000-fold to a final specific activity of 11 mU/mg protein (at 20 degrees C) and gave a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme was a dimer with a native molecular mass of 142 kDa and a subunit molecular mass of 67 kDa. The purified enzyme showed negligible fructose-2,6-bisphosphatase (FBPase-2) activity, although the activity ratio of PFK-2 to FBPase-2 was 0.625 in crude extracts. In response to environmental anoxia, the activity of PFK-2 dropped in all organs to 34-56% of the corresponding aerobic value (half-time was 2 h in gill), and the Michaelis constant for fructose 6-phosphate increased by 50% (to 92 microM in gill). These changes paralleled decreases in organ fructose 2,6-bisphosphate concentration and pyruvate kinase activity and contribute to the overall glycolytic rate depression induced by anoxia in this facultative anaerobe. In vitro treatment of the anoxic form of hepatopancreas PFK-2 with alkaline phosphatase increased enzyme activity, suggesting that the aerobic and anoxic enzyme forms are interconverted by reversible protein phosphorylation. However, the protein kinase involved in this process is not yet known; incubation of aerobic PFK-2 with Mg-ATP plus adenosine 3',5'-cyclic monophosphate-dependent protein kinase or protein kinase C did not alter enzyme activity.
 ...
PMID:Inactivation of 6-phosphofructo-2-kinase during anaerobiosis in the marine whelk Busycon canaliculatum. 164

Several methods for the permeabilization of Saccharomyces cerevisiae M1 were compared. Cells were permeabilized in the presence of 3% toluene/mercaptoethanol, and the activities of 6-phosphofructo-2-kinase, fructose-2,6-bisphosphatase and alkaline phosphatase were measured during growth of yeast on glucose. In the exponential phase of growth, the specific activities of 6-phosphofructo-2-kinase and fructose-2,6-bisphosphatase decrease significantly. The specific activities of 6-phosphofructo-2-kinase and high-affinity fructose-2,6-bisphosphatase increase again during the transition phase and reach maximum values in the stationary phase. In contrast to the specific activities, the activity concentrations of 6-phosphofructo-2-kinase and fructose-2,6-bisphosphatase remain nearly constant in the exponential phase, but increase in the transition and the stationary growth phase. The concentration of fructose-2,6-bisphosphate drops from about 6 microM in the exponential phase to very low levels in the transition phase, but increases slightly in the stationary phase. In Saccharomyces cerevisiae M1 several fructose-2,6-bisphosphate degrading activities were measured differing in the behaviour during growth on glucose, in the pH-optimum and the inhibition by fructose-6-phosphate.
 ...
PMID:Fructose-2,6-bisphosphate metabolism in permeabilized yeast cells. 166 44

The phosphorylation status of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphate 2-phosphatase (EC 2.7.1.105/ EC 3.1.3.46) in rosette leaves of Arabidopsis was examined. Immunoblotting with specific antisera detected 96-kDa and 92-kDa bands in the crude protein extracts from rosette leaves of Arabidopsis. Incubation of protein samples with alkaline phosphatase before SDS-PAGE reduced the 96-kDa band with concomitant increase of the 92-kDa band, suggesting that the former is a phosphorylated form of the latter. In accordance with this result, 96-kDa and 92-kDa bands were immuno-precipitated from the crude protein extracts from [(32)P]orthophosphate-labeled rosettes of Arabidopsis; and, the former was heavily labeled, the latter faintly labeled. Analysis of phospho-amino acid residues derived from the [(32)P]-labeled 96-kDa band revealed that the phosphorylation occurred on serine and threonine residues, excluding the possibility that the phosphorylated band represent a phospho-histidine intermediate that is known to form in the phosphatase reaction. The relative level of the 96-kDa band over the 92-kDa band in whole rosette extracts changed diurnally and was highest at the beginning of nighttime. Furthermore, the 96-kDa band was highly enriched in the extracts of very young rosette leaves, suggesting that the phosphorylation status of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphate 2-phosphatase is regulated physiologically and developmentally in Arabidopsis.
 ...
PMID:Phosphorylation of a bifunctional enzyme, 6-phosphofructo-2-kinase/fructose-2,6-bisphosphate 2-phosphatase, is regulated physiologically and developmentally in rosette leaves of Arabidopsis thaliana. 1167 18