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)

The activity of acid phosphatase in the testicular parenchyma of cattle was found to be higher than that in the endometrium. The acid phosphatase of either tissue broke up p-nitrophenylphosphate at a rate twice as high as that reached for di-sodium phenylphosphate. Hydrolysis of phenolphthalein diphosphate was slower and that of beta-glycerophosphate very slow. Two optimum pH values and two isozymes were recordable from acid phosphatase in testicular supernatant and three optimum pH values as well as three isozymes from that in endometrial supernatant. Even concentrations pf 0.2 mM of copper and mercury ions were strongly inhibiting the acid phosphatase, whereas lead and cadmium ions proved less effective. The activity of acid phosphatase from testes dropped by 24 per cent and that from the endometrium by 16 per cent over eight weeks of storage at -20 degrees C. The average activity of alkaline phosphatase in the endometrium was much higher than that in testicular parenchyma. Alkaline phosphatase from testes exhibited the shortest break-up time for p-nitrophenylphosphate, whereas disodium-phenylphosphate was broken up at the highest rate by endometrial alkaline phosphatase. Two isozymes of alkaline phosphatase were recordable each from the testes and endometrium.
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PMID:[Properties and isozymes of acid and alkaline phosphatase in cattle testes and endometrium]. 2 59

When the pH of growth medium containing a limited amount of inorganic phosphate is kept below 3.0, cells of Saccharomyces cerevisiae produce repressible alkaline phosphatase but no repressible acid phosphatase. The same cells produce acid phosphatase immediately on shifting the medium pH to 4.0 or above. Like intact cells, spheroplasts prepared from cells grown at pH 3.0 or 4.5 in medium with a limited amount of inorganic phosphate in suspension begin production of acid phosphatase immediately after pH shift from below 3.0 to 4.0 whereas sheroplasts from cells grown in inorganic phosphate-rich medium showed a prolonged lag period (3 h). The enzyme formation on the pH shift was sensitive to cycloheximide. No significant differences could be detected in cellular growth or in incorporation of 3H-L-lysine or 14C-adenine between cells cultivated at pH 3.0 and 4.5. These results along with the fact that the expression of structural genes of repressible acid and alkaline phosphatases is controlled by a common genetic regulatory system, at least in part, indicate that the genetic regulatory system operates to express the structural genes even at low pH, though the expression of repressible acid phosphatase is interrupted. Coupled experiments of temperature and pH shifts with the temperature-sensitive mutants of the regulatory genes suggest that the acidic pH affects the function of the cytoplasmic products of those genes in the expression of the structural gene. Based on these observations, a revised model involving the simultaneous functioning of the regulatory factors was suggested for the genetic regulation of repressible acid phosphatase synthesis.
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PMID:Disturbance of the machinery for the gene expression by acidic pH in the repressible acid phosphatase system of Saccharomyces cerevisiae. 2 17

31P nuclear magnetic resonance spectra and enzymatic activities are compared for alkaline phosphatase (orthophosphoric-monoester phosphohydrolase (alkaline optimum), EC 3.1.3.1) species with different zinc contents. The enzyme containing two Zn2+ per protein dimer exists in two forms; one, prepared by dialysis of native enzyme, has full enzymatic activity and a 31P magnetic resonance spectrum similar to but distinguishable from that of the native enzyme containing four or more Zn2+. The other form, prepared by restoring two Zn2+ to apoenzyme, has low enzymatic activity and a 31P magnetic resonance spectrum that indicates stoichiometric binding of phosphate, but otherwise altered properties. Reconstituted enzyme with four Zn2+ is similar to but distinguishable from native enzyme with four Zn2+. Chromatography on DEAE-cellulose can separate apoenzyme and enzyme containing two Zn2+ and suggests that the binding of a pair of Zn2+ is cooperative.
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PMID:Zinc stoichiometry in Escherichia coli alkaline phosphatase. Studies by 31P NMR and ion-exchange chromatography. 2 75

Activities of 9 enzymes were determined biochemically in the endometrium. In Trial I (five women) 25 mg progesterone were injected i.m. on day 9 of the cycle; and endometrial biopsy taken 24 hours later was compared with endometrium from day 10 and day 21, taken in two untreated cycles from the same volunteers. Similarly, in Trial II (five women) 50 mg progesterone were injected on day 9, biopsy taken on day 11 and compared with days 11 and 21 from untreated cycles. The specific activites of lactate dehydrogenase, isocitrate dehydrogenase (ICDH), malate dehydrogenase, glutamate dehydrogenase, beta-glucuronidase, acid phosphatase (ACP) and alkaline phosphatase (AP) were significantly higher in the secretory phase. Twenty-five milligrams progesterone (after 24 hours) caused increases of some enzymes, significant only for AP. Fifty milligrams (after 48 hours) increased significantly the activity of ICDH and ACP. Biochemical changes, especially increase of ICDH, can be used for detection of the effect of progesterone on the endometrium.
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PMID:Effect of endogenous and exogenous progesterone on human endometrial enzymes. 3 Jul 6

Two isoenzymes of rat liver acid phosphatase (orthophosphoric-monoester phosphohydrolase (acid optimum) EC 3.1.3.2) have been purified to homogeneity, at least one of these for the first time. Both of the rat liver isoenzymes have identical specific activities towards p-nitrophenyl phosphate. Molecular weights of the native enzymes are 92 000 for rat liver isoenzyme I and 93 000 for isoenzyme II, while the subunit molecular weights are 51 000 and 52 000 respectively. Data on substrate specificity and pH dependence are presented for the homogeneous canine prostatic enzyme, which is also isolated as a dimeric enzyme of (native) molecular weight 89 000. Carbohydrate analysis data are presented for canine prostatic acid phosphatase and it is further noted that both isoenzymes of rat liver acid phosphatase are also glycoproteins. The amino acid compositions of the two rat liver isoenzymes are presented together with those of the similar dimeric acid phosphatase of human liver and of canine prostate. Comparison of these results with published data for the amino acid composition of human prostatic acid phosphatase shows substantial similarities. However, significant differences are seen in the amino acid composition of rat liver acid phosphatase isoenzyme I as compared to a previous literature report. Most notably, 17 histidine residues are found per mol of isoenzyme I and 18 for isoenzyme II.
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PMID:Dimeric nature and amino acid compositions of homogeneous canine prostatic human liver and rat liver acid phosphatase isoenzymes. Specificity and pH-dependence of the canine enzyme. 3 Nov 80

A phosphatase, hydrolyzing pyridoxal-5-phosphate (P5P), a physiologically active component of the vitamin B6 complex and an essential co-enzyme in the synthesis of neurotransmitters, has been localized cytochemically in the perikarya of neurons in the peripheral, autonomic and central nervous systems of the rat. Neurons in dorsal root ganglia, sympathetic ganglia and ventral horn of spinal cord were studied by light and electron microscopy, while Purkinje cells, neurons in the dentate nucleus of the cerebellum, thalamus, and hypothalamus were studied by light microscopy only. Optimal conditions for demonstrating this activity in aldehyde-fixed tissue were determined with dorsal root ganglia. At the optimal pH of 5.0, neurons in these ganglia and in all other neurons studied show pyridoxal-5-phosphatase (P5Pase) activity in GERL. Small neurons in dorsal root ganglia also display enzyme activity in the endoplasmic reticulum (ER); activities in GERL and ER are also appreciably high at neutral pH. Small and large neurons in these ganglia, and neurons of sympathetic ganglia, show variable P5Pase activity in the Golgi apparatus. These localizations differ from the usual sites of both acid phosphatase and alkaline phosphatase activities. The P5Pase activity, demonstrated cytochemically, is a new acid hydrolase activity in GERL.
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PMID:Pyridoxal phosphatase: cytochemical localization in GERL and other organelles of rat neurons. 3 96

Alkaline phosphatase from calf intestine (orthophosphoric-monoester phosphohydrolase (alkaline optimum), EC 3.1.3.1) is reversibly inhibited at pH 8.0 by incubation with chelating agents. Complete reactivation may be achieved by stoichiometric addition of Zn2+. Atomic absorption spectrometry was used to demonstrate the linear correlation between Zn2+ content and degree of reactivation. The reversibly inhibited enzyme contained 1 Zn2+ per subunit whereas 2 Zn2+ were found in both the reactivated and the native enzyme. At more alkaline pH-values, inactivation by chelating agents becomes irreversible; under such conditions the inactivated alkaline phosphatase still contains 1 Zn2+ per subunit. The conformational changes resulting from the loss of Zn2+ and leading to irreversible inactivation were investigated by optical rotatory dispersion, immunological techniques, and ultraviolet and fluorescence spectroscopy. Azocoupling of the alkaline phosphatase with diazonium-1-H-tetrazole and Zn2+ content measurement of azocoupled enzyme probes indicated that 2 histidine residues per subunit are involved in binding of the catalytically important Zn2+.
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PMID:The role of Zn(II) in calf intestinal alkaline phosphatase studied by the influence of chelating agents and chemical modification of histidine residues. 3 15

Large amounts (66-97%) of marker enzymes such as alkaline phosphatase, 5'-nucleotidase, phosphodiesterase I, and gamma-glutamyl transpeptidase of bovine milk fat globule membrane (MFGM) were selectively solubilized by nonionic detergents such as Triton X-100, Tween 20, Nonidet P-40, Liponox NCK, and Emulgen 109-P. On the other hand, the extractability of MFGM protein with these detergents was less than 50%. Judging from the recovery of total activity, it is likely that alkaline phosphatase, phosphodiesterase I, and gamma-glutamyl transpeptidase are activated by nonionic detergents, whereas 5'-nucleotidase is somewhat inhibited by the detergents, except for Tween 20, and acid phosphatase is strongly inhibited by all detergents. In addition, solubilization of the protein with the nonionic detergents was found to be somewhat selective by SDS-polyacrylamide gel electrophoresis. There was no appreciable difference between the five brands of nonionic detergents used as regards the extractability of protein and the enzymatic activity of the extracted marker enzymes of MFGM, except that the solubilizing ability of Tween 20 was relatively low.
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PMID:Selective extraction of marker enzymes of bovine milk fat globule membrane by nonionic detergents. 3 79

Treatment of homogenous human prostatic acid phosphatase (orthophosphoric-monoester phosphohydrolase (acid optimum), EC 3.1.3.2) with low concentrations of Woodward's reagent K (N-ethyl-5-phenylisoxazolium-3'-sulfonate) leads to a rapid loss of enzymic activity. The rate of inactivation of the enzyme is reduced in the presence of the competitive inhibitors phosphate and L-(+)-tartrate, but not in the presence of non-inhibitory D-tartrate. Measurement of the ethylamine produced upon hydrolysis of enzyme modified in the presence of D- and of L-tartrate permitted the quantitative estimation of the number of carboxylic acid residues at the active site. The data indicate that two carboxyl groups per (dimeric) enzyme molecule are essential for catalytic activity. It is proposed that one function of the active site carboxyl group may be to protonate the leaving alcohol or phenol portion of the phosphomonoester substrate during the formation of the covalent phosphoenzyme intermediate.
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PMID:An essential carboxylic acid group in human prostate acid phosphatase. 3 4

Purified chondrocytic alkaline phosphatase (orthophosphoric-monoester phosphohydrolase (alkaline optimum), EC 3.1.3.1) from bovine fetal epiphyseal cartilage hydrolyzes a variety of phosphate esters as well as ATP and inorganic pyrophosphate. Optimal activities for p-nitrophenyl phosphate, ATP and inorganic pyrophosphate are found at pH 10.5, 10.0 and 8.5, respectively. The latter two substrates exhibit substrate inhibition at high concentrations. p-Nitrophenyl phosphate demonstrates decreasing pH optima with decreasng substrate concentration. Heat inactivation studies indicate that both phosphorolytic and pyrophosphorolytic cleavage occur at the same site on the enzyme. Mg2+ (0.1-10.0 mM) and Mn2+ (0.01-0.1 mM) show a small stimulation of p-nitrophenyl phosphate-splitting activity at pH 10.5. Levamisole, Pi, CN-, Zn2+ and L-phenylalanine are all reversible inhibitors of the phosphomonoesterase activity. Pi is a competitive inhibitor with a Ki of 10.0 mM. Levamisole and Zn2+ are potent non-competitive inhibitors with inhibition constants of 0.05 and 0.04 mM, respectively. The chondrocytic alkaline phosphatase is inhibited irreversibly by Be2+, EDTA, EGTA, ethane-1-hydroxydiphosphonate, dichloromethane diphosphonate, L-cysteine, phenyl-methylsulfonyl fluoride, N-ethylmaleimide and iodoacetamide. NaCL, KCL and Na2SO4 at 0.5-1.0 M inhibit the enzyme. At pH 8.5, the cleavage of inorganic pyrophosphate (pyrophosphate phosphohydrolase, EC 3.6.1.1) by the chondrocytic enzyme is slightly enhanced by low levels of Mg2+ and depressed by concentrations higher than 1mM. Ca2+ show only inhibition. Similar effects of Mg2+ and Ca2+ on the associated ATPase (ATP phosphohydrolase, EC 3.1.6.3) activity were observed. Arrhenius studies using p-nitrophenyl phosphate and AMP as substrates have accounted for the ten-fold difference in V in terms of small differences in both the enthalpies and entropies of activation which are 700 cal/mol and 2.3 cal/degree per mol, respectively.
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PMID:Enzymatic characterization of the chondrocytic alkaline phosphatase isolated from bovine fetal epiphyseal cartilage. 4 Jun 3


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