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

A new species of orthophosphate repressible extracellular 5'-nucleotidase (5'-ribonucleotide phosphohydrolase, EC 3.1.3.5) was found to be released into mycelial culture media when a wild type strain of Neurospora crassa was grown on limiting amounts of phosphate. The production of 5'-nucleotidase and extracellular acid and alkaline phosphatase was inhibited by the addition of rifampicin when it was added at the later stage of mycelial growth, but not when it was added at a very early stage. The 5'-nucleotidase and extracellular alkaline phosphatase were partially purified and characterized. pH optimum of the former was 6.8 and that of the latter was higher than 10.0. The 5'-nucleotidase activity was inhibited by ethylenediaminetetraacetate (EDTA) and ZnCl2 at pH 6.8 and stimulated by MnCl2 and CoCl2 at pH 4.0. Alkaline phosphatase activity was stimulated by EDTA, MgCl2, CoCl2 and MnCl2. 5'-nucleotidase activity was stimulated by EDTA, MgCl2, CoCl2 and MnCl2. 5'-nucleotidase hydrolyzed various 5'-nucletides but not 3'-nucleotides or other various phosphomono- and diester compounds. Alkaline phosphatase hydrolyzed all the phosphomonoester compounds tested. Mutants, nuc-1 and nuc-2, which were originally isolated by the inability to utilize RNA or DNA as a sole source of phosphate, were unable to produce 5'-nucleotidase or six other repressible enzymes reported previously. These mutants showed no or significantly reduced growth on orthophosphate-free nucleotide media depending on the number of conidia inoculated, mainly because of loss of ability to produce these repressible extracellular phosphatases.
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PMID:Control of the production and partial characterization of repressible extracellular 5'-nucleotidase and alkaline phosphatase in Neurospora crass. 13 48

For the purpose of detecting the synthesis of zinc metalloenzymes after zinc supplementation in an experiment using rats the animals were first depleted for 15 days and subsequently injected a labelled zinc salt solution (65Zn-ZnCl2) in a dosis of 0.4 mg (in terms of Zn) and with an activity of 3.0 muCi/100microliter. After a 5-day depletion period, the activity of the metallo-enzymes alkaline phosphatase in plasma and in the femur and carboxy-peptidase A and B in the pancreatic gland was found to rise at the same rate as the 65Zn-measuring rate in plasma, femur and pancreatic gland. By calculating correlations this interdependence was demonstrated. Thus the highly significant correlation coefficients prove for these metalloenzymes that a synthesis with the injected zinc salt has taken place whilst for carbo-anhydrase in blood this evidence was not furnished. As the zinc dosis is not exclusively used for the enzyme synthesis, but additional 65Zn is incorporated into the individual organs, it does not appear to be possible to draw conclusions from the 65 Zn-measuring rate in the individual organs on the intermediary availability.
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PMID:[Demonstration of zinc-metalloenzyme syntheses after zinc supplements for deficient animals by means of measurement of the incorporation of 65Zn in various organs]. 41 27

Methods have been sought to perturb the level of phosphohistones. ZnCl2 (10 mM) exhibits histone phosphate phosphatase in vivo in HTC cells and leads to hyperphysiological levels of F1 phosphohistone. Treatment of tissue culture cells with this concentration of ZnCl2 leads to a reduction in medium pH to 6.4. Control experiments have indicated that HTC cells grow efficiently at this pH and that the reduction of pH does not produce the hyperphosphorylated state per se. The optimum conditions for the ZnCl2 effect are described. That the effect of ZnCl2 on the heterogeneity of F1 histone is due to an effect on phosphorylation was demonstrated by the observation that the entire effect is abolished by treatment with alkaline phosphatase. The site of phosphorylation is in the carboxy-terminal end of the F1 molecule. The inhibitory effect of ZnCl2 on F3 phosphorylation in metaphase cells is also described.
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PMID:Production of high levels of phosphorylated F1 histone by zinc chloride. 77 24

The effects of divalent cations and of some inhibitors on the activities of alkaline phosphatase and ATPase were examined in rat jejunal brush-border membranes (BBM) isolated by tha Ca(2+)-(BBMCa) or the Mg(2+)-precipitation method (BBMMg). Similar results were found in BBMCa and BBMMg though generally higher in BBMCa. Alkaline phosphatase activity was stimulated by 5 mM MgCl2 (30% to 44%), but not by 5 mM CaCl2 or 0.1 mM ZnCl2, at pH 9.5 or 7.4. ATPase activity was equally stimulated by 5 mM MgCl2 and by 5 mM CaCI2 (about 150%). Alkaline phosphatase activity was significantly inhibited by 1 mM vanadate, 5 mM diamox, 5.0 mM L-leucine and 1 mM theophylline. In contrast, Ca(2+)-ATPase and Mg(2+)-ATPase activities were not depressed by those alkaline phosphatase inhibitors, but were inhibited by 0.1 mM trifluoperazine (more than 70%). 0.1 mM ZnCl2 also appeared to be inhibitory to Ca(2+)-ATPase and Mg(2+)-ATPase, but not to alkaline phosphatase activity even in the presence of Ca2+ and Mg2+. These results suggest that Ca(2+)-ATPase and Mg(2+)-ATPase activities of the rat jejunal BBM are not merely manifestations of alkaline phosphatase, but rather belong to (a) distinct enzyme(s).
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PMID:Alkaline phosphatase and ATPases in brush-border membranes of rat jejunum: distinct effects of divalent cations and of some inhibitors. 138 82

Pregnant rat dams were divided into four groups on the 3rd day of gestation. Group 1 dams were fed a 20% protein diet as controls. Dams of group 2 were fed a 20% protein diet supplemented with zinc (0.6 g ZnCl2/kg diet). Group 3 dams were fed a 20% protein diet supplemented with caffeine (2 mg/100 g body weight) and dams of group 4 were fed a 20% protein diet supplemented with both caffeine and zinc. Fetuses were surgically delivered on day 22, and brains were removed and analyzed for alkaline phosphatase activity, protein, zinc, cholesterol and DNA concentrations. Fetal brain caffeine levels, as well as maternal and fetal plasma caffeine levels, were determined in caffeine-supplemented groups. The body weight of group 4 and brain weights of groups 3 and 4 were higher than those of groups 1 and 2. Alkaline phosphatase activity of group 3 was less than that of group 1. The brain zinc concentration of group 2 was higher than in the other groups, but that of group 4 was less than that of group 1. The present study indicated that the supplementation of caffeine to the maternal diet decreased zinc levels in the fetal brain, and the addition of extra zinc to this diet did not return the zinc level to that of the control level as we had expected. In addition, the supplementation of caffeine and zinc together increased the body weights of the fetuses compared to the controls, but the addition of only one of these substances had no effect, suggesting that the combination of caffeine and zinc may have unique effects on fetal growth.
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PMID:Relationship of prenatal caffeine exposure and zinc supplementation on fetal rat brain growth. 148 56

We have produced a batch of lyophilized alkaline phosphatase (AP) for use as an enzyme reference material. The enzyme was partly purified from pig kidney to a specific activity of 400 U/mg of protein and is essentially free from contaminating enzyme activities. The kinetic properties of the preparation are very close to those of the enzyme present in human serum. The partly purified AP was lyophilized in a matrix containing bovine serum albumin (40 g/L), MgCl2, ZnCl2 and NaCl. The vial-to-vial variability with respect to the catalytic concentration of the final product was 0.008. The predicted annual relative loss of activity was less than 0.01% at -20 degrees C and 0.04% at 4 degrees C. This material was certified using the IFCC proposed method. The certification procedure involved 19 laboratories throughout the world. The certified alkaline phosphatase catalytic concentration in the reconstituted material was 254 U/L with a 0.95 confidence interval of +/- 6 U/L.
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PMID:Certification of an enzyme reference material for alkaline phosphatase (CRM 371). 204 88

Renal brush border membrane vesicles (BBMV) of the dog possess at least two ATPase activities. In the present study, we have examined the effect of pH, ions, and inhibitors on the activity of ATPase in BBMV. Two different sets of conditions were identified that produced stimulation of ATPase activity. A unique stimulation of BBMV ATPase activity occurred at acidic pH in the presence of 1 mM ZnCl2. In the absence of Zn2+, a second ATPase activity was stimulated by alkaline pH values with peak stimulation occurring between pH 8.5 and 9.0. The results suggest that the alkaline pH-stimulated hydrolysis of ATP probably represents the activity of BBMV alkaline phosphatase. The unique acidic pH + Zn2(+)-stimulated ATPase activity must represent the activity of a second protein other than the alkaline phosphatase, since purified alkaline phosphatase did not show this activity. The biochemical identity and physiological function of this renal BBMV ATPase activity remain to be determined, but it may be an ecto-ATPase.
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PMID:Stimulation of canine kidney BBMV ATPase activity by acidic pH in the presence of Zn2+: an ATPase activity distinct from transport ATPases and alkaline phosphatase that may be an ecto-ATPase. 215 Feb 16

An isoelectric focusing technique for human neutrophil alkaline phosphatase isoenzymes is described. After sonication with Zwittergent 3-12, butanol extraction and ultracentrifugation, dialysis of cytosols precedes focusing. Focusing patterns show a heterogeneity with two enzymatic activity areas: a main component at pI 6.7-6.8 with a minor component at pI 4.8-5.0 which is difficult to visualize due to its sensitivity to experimental conditions. The addition of 3 mmol/l ZnCl2 to the agarose gel improved the staining of focused bands and in particular the anodic component.
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PMID:Isoelectric focusing of human neutrophil alkaline phosphatase isoenzymes in agarose gel. 340 28

Granulocyte alkaline phosphatase (GAP) was extracted from the leukocyte suspensions of 15 subjects with chronic myeloid leukemia (CML), determining the Zn content by atomic absorption spectrophotometry. The purified enzymatic preparation was dialyzed against a ZnCl2 solution (.01 mg%) in TRIS-HCl 0.1 M, pH 7.5, for 48 hours. After dialysis Zn concentration and GAP activity reached normal values. This suggests that the GAP molecule isolated from CML subjects is not altered as it is able to receive at most 2 Zn moles responsible for the enzymatic function.
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PMID:Alkaline phosphatase activity improved by the addition of zinc in granulocytes from leukemic subjects (in vitro study). 659 61

Many researches have shown the role of some bivalent ions on the structure and function of alkaline phosphatase. For this reason we considered interesting to assay the effect of Zn++ and Mg++, at various concentrations, on the activity of alkaline phosphatase (APase) from different sources. The isoenzymes of alkaline phosphatase used for the experiments were from rat kidney and bone, from calf intestinal mucosa and from Escherichia coli. In order to investigate the effect of Zn++ and Mg++ on the enzyme activity, the two ions were removed using EDTA as chelating agent. The residual enzymatic activity was measured after having preincubated for 15 min the enzyme with EDTA at a final concentration of 0.05 mM, 0.1 mM, 0.5 mM, 5 mM, 25 mM. The reactivation of the enzyme was studied using as reference a sample, in which the final concentration of EDTA was 5 mM. In these series of experiments the enzymatic activity was assayed after a preincubation of the reaction mixture with ZnCl2 10 mM, MgCl2 10 mM and ZnCl2 +MgCl2 10 mM. The inactivation in the time of the enzyme by 5 mM EDTA was also studied. The results obtained show that APase from intestinal mucosa maintained, at the lower concentrations of EDTA (0.05, 0.1 and 0.5 mM), a residual activity higher than that of the enzymes of other source. Moreover, whilst the activity of the mucosal enzyme was completely restored by the addition of Zn++, the complete reactivation of the other enzyme activities was obtained only by the addition of Zn++ and Mg++ together. Concerning the inactivation by EDTA during the time, it was shown that APase from calf intestinal mucosa was inactivated after 60 min of incubation, while the enzymes from other sources lost completely their activity after 10 min.
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PMID:[Influence of Zn++ and of Mg++ on alkaline phosphatase activity of different origins]. 700 69


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