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 pancreatic ribonuclease digest of (14)C-labeled tobacco necrosis virus RNA was fractionated according to charge by column chromatography. Individual fractions were dephosphorylated with alkaline phosphatase and rechromatographed. The fraction, originally containing oligonucleotides with seven negative charges, separated into two components corresponding to five (-5) and two negative charges (-2). The -5 fraction was derived from the internal oligonucleotides while the -2 fraction must have originated from a 5'-pyrophosphorylated terminal trinucleotide. The sequence of this terminal trinucleotide was determined by column chromatography on DEAE-cellulose in a triethyl ammonium carbonate gradient, using the appropriate markers. The radioactivity chromatographed with a (ApGp)U marker. The order of the Ap and Gp was determined after ribonuclease T(1) and alkaline phosphatase digestion. The radioactivity in the product chromatographed with an ApG marker. The 5'-terminus of tobacco necrosis virus RNA was therefore determined as ppApGpUp..., which is identical to the terminus of the RNA of its satellite virus as previously determined (J. Mol. Biol., 38, 59 (1968); Science, 160, 1452 (1968)). The 5' pyrophosphate in both viruses was probably formed by an in vivo enzymatic removal of a gamma-phosphate from a triphosphate, and its presence in both viruses suggested a common site of synthesis. The identity of the 5'-terminal sequences is considered not to be fortuitous and is discussed from the standpoint of their role as a recognition site for the virus-specific RNA replicase.
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PMID:Identity of the 5'-terminal RNA nucleotide sequence of the satellite tobacco necrosis virus and its helper virus: possible role of the 5'-terminus in the recognition by virus-specific RNA replicase. 527 92

Analytical subcellular fractionation of tissue whole homogenates and microanalysis of organelle marker enzymes were used to study the activity and subcellular localization of enzymes implicated in HCO3 secretion in rat duodenal and gastric antral mucosae. The following organelles, characterized by their marker enzymes, were located in the density gradients: cytosol (lactate dehydrogenase), plasma membrane (5'-nucleotidase), peroxisomes (catalase), mitochondria (succinate dehydrogenase), endoplasmic reticulum (Tris-resistant alpha-glucosidase), lysosomes (N-beta-acetylglucosaminidase), and brush-border membrane (Zn2+-resistant alpha-glucosidase and alkaline phosphatase). Compared with gastric antrum, rat duodenal mucosa contained over twice the activity of HCO3-ATPase and of Na+-K+-ATPase but less than one-tenth the activity of carbonic anhydrase. Duodenal HCO3-ATPase activity was observed in both mitochondrial and brush-border membrane fractions, whereas antral HCO3-ATPase activity was confined to mitochondria. Na+-K+-ATPase activity was found largely in the basolateral membrane (duodenum) and plasma membrane (antrum). In both tissues carbonic anhydrase activity was localized to the cytosolic fraction. These observations offer further evidence that differing biochemical mechanisms underlie HCO3 secretion by gastric and duodenal epithelia.
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PMID:Activities and subcellular localizations of enzymes implicated in gastroduodenal bicarbonate secretion. 608 73

Na+,K+-ATPase, HCO3(-)-ATPase, Ca2+,Mg2+,-ATPase, Ca2+-ATPase, and alkaline phosphatase activities were measured in cultures of osteoblastlike cells treated with fluoride and cortisol separately and in combinations. Low concentrations of cortisol increased HCO3- -ATPase (10(-11) to 10(-18) M cortisol) and alkaline phosphatase (10(-11) to 10(-9) M cortisol) activities, but higher cortisol concentrations reduced these activities. Na+,K+-ATPase, Ca2+,Mg2+-ATPase, and Ca2+-ATPase activities tended only to be reduced by cortisol. Fluoride (10(-6) and 5 X 10(-6) M) increased HCO3(-)-ATPase and alkaline phosphatase activities, but these activities were similar to controls in the presence of 10(-5) M fluoride. Ca2+,Mg2+-ATPase activity was decreased and Na+,K+-ATPase activity was increased as the concentration of fluoride increased (10(-6) to 10(-5) M). Preliminary experiments with fluoride indicated that lower concentrations (10(-7) M) were without effect. Cortisol concentrations of 10(-9) and 10(-8) M were chosen for studies with combinations of cortisol and fluoride because the effects of these concentrations on alkaline phosphatase activity were opposite, i.e. 10(-9) M increased whereas 10(-8) M decreased activity. Fluoride concentrations of 10(-6), 5 X 10(-6), and 10(-5) M were chosen because a peak of alkaline phosphatase activity occurred at 5 X 10(-6) M fluoride. Higher (10(-4) M) and lower (10(-7) M) fluoride concentrations were without effect. The effects of combinations of cortisol and fluoride depend on the enzyme activity measured. Fluoride (10(-6) M) combined with cortisol (10(-9) M) produced a peak of Na+,K+-ATPase activity. The increased activity obtained with all concentrations of fluoride alone was preserved when fluoride was combined with 10(-8) M cortisol, although the activity tended to be reduced at 5 X 10(-6) and 10(-5) M fluoride. HCO3(-)-ATPase activity was increased by fluoride combined with 10(-8) M cortisol and decreased by fluoride combined with 10(-9) M cortisol compared to the activities obtained with fluoride alone. The decrease in Ca2+,Mg2+-ATPase activity caused by fluoride alone was prevented by 10(-9) and enhanced by 10(-8) M cortisol, although all treatments produced the same activity at 10(-5) M fluoride. Ca2+-ATPase activity tended to be increased by combinations of fluoride and cortisol, but significantly so only at 10(-5) M fluoride in combinations with 10(-8) and 10(-9) M cortisol.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Effects of cortisol and fluoride on ion-transporting ATPase activities in cultured osteoblastlike cells. 609 29

Phosphohydrolase activity of a highly enriched commercial preparation of calf intestinal alkaline phosphatase was stimulated in the presence of HCO3. SO4, Cl, SCN, and acetate did not stimulate hydrolysis, whereas SO3 exhibited a bimodal effect, stimulating at low (25mM) concentration but inhibiting at high (100 mM) concentration. The pH optimum of this stimulation by HCO3 or SO3 was 8.5--9.0 and was maximal at a Mg concentration of 0.5 mM. HCO3 increased the Vmax of the reaction without changing the Km for ATP. ATP, GTP, UTP, and xanthosine triphosphate were equally effective as substrates, whereas AMP and p-nitrophenyl phosphate were much less effective. Alkaline phosphatase activity was inhibited by L-cysteine and L-phenylalanine, compounds that also inhibited the HCO3-ATPase activity of the preparation. Passage of the commercial preparation through an anion-exchange column yielded a fraction with enriched alkaline phosphatase and HCO3-ATPase activities; this fraction proved to be a single protein on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, on isoelectric focusing, and by immunologic techniques. These studies strongly suggest that alkaline phosphatase and anion-stimulated phosphohydrolase activities are properties of the same protein in small intestine. It is possible that alkaline phosphatase may function as a HCO3-ATPase involved in intestinal absorption and secretion.
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PMID:Anion-stimulated phosphohydrolase activity of intestinal alkaline phosphatase. 615 12

The sensitivity of the dental pulp enzyme to heat was similar to that of enzymes from bone and kidney; alkaline phosphatases from liver and intestine were more stable to heat. L-Homoarginine strongly inhibited the enzyme activities from pulp, bone, kidney and liver but did not affect intestinal enzyme activity. Increasing the molarity of carbonate buffer or glycine buffer in the assay solution decreased intestinal alkaline phosphatase activity more markedly than enzyme activities of other tissues. In 100 mM glycine-NaOH buffer, the effects of Zn2+, Mg2+ and Ca2+ on pulp alkaline phosphatase activity were similar to those on the enzyme activities of bone, kidney and liver. The electrophoretic pattern of the pulp enzyme on sodium dodecyl sulphate-gels was identical with that of bone enzyme and differed from the patterns of enzymes from other tissues. These results suggest that the dental pulp alkaline phosphatase may be the same as bone enzyme.
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PMID:A comparison of the alkaline phosphatases of rat dental pulp, bone, kidney, liver and intestine. 619 45

Administration of lithium carbonate, 750 mg daily, during 10 days to 25 patients with essential granulocytopenia, induced an increase of the total leukocyte count, of the absolute count of neutrophils and of the number of neutrophils phagocytizing Staphylococcus aureus Oxford in vitro. An enhancement of acid phosphatase activity in the neutrophils was noted both in the patients and the healthy subjects in the control group. In the patients, the counts of neutrophils exhibiting a positive enzymatic reaction with regard to beta-glucuronidase, myeloperoxidase and alkaline phosphatase were also increased after treatment with lithium carbonate. Based on these results, the authors recommend the clinical application of this treatment in patients with granulocytopenia.
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PMID:Effect of lithium carbonate on the functional state and the enzymatic equipment of neutrophils in patients with granulocytopenia. 624 67

In a double-blind trial, 327 patients (57 men) over 65 (mean age 79.5) years received all possible combinations of calcium carbonate 3 g, vitamin D3 1000 iu, methandienone 2.5 mg and/or placebos daily for 9 months. The higher incidence of bone fractures in the placebo group was not significant. Serum calcium, phosphorus, creatinine, aspartate aminotransferase and alkaline phosphatase were followed: the greatest changes occurred with methandienone, which thus reduced osteoporotic activity and increased the muscular mass most effectively; calcium carbonate had the poorest effect. Surprisingly, coronary mortality was higher among those taking all three active substances. With two treatments the increase was not significant, but when both the groups receiving a combination of any two of the treatments were compared with those taking only one or neither of these two treatments, a significant increase in coronary deaths was seen, most significant (P less than 0.001) in those receiving vitamin D3 and methandienone.
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PMID:Calcium, vitamin D and anabolic steroid in treatment of aged bones: double-blind placebo-controlled long-term clinical trial. 634 29

Hamster molar tooth germs were tested in vitro for their capacity to incorporate 45Ca, 32PO4 and H14CO3 into their mineral. Concomitantly, the activities of alkaline phosphatase and carbonic anhydrase were measured in the cultured tooth germs. Incorporation of calcium and phosphate into the dental mineral increased with time in culture (0-10 days), whereas carbonate incorporation decreased slightly. Alkaline phosphatase and carbonic anhydrase increased with time. These results suggest that carbonic anhydrase is probably not involved in carbonate deposition, but in carbonate depletion of the dental mineral, carbonate being probably replaced by phosphate.
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PMID:Carbonate incorporation and carbonic anhydrase activity in developing hamster molars in vitro. 640 75

There are conflicting data on the effects of lithium on bone metabolism. Bone formation is known to be reflected by the activity of alkaline phosphatase of the bone tissue. We have found significant differences in mean serum alkaline phosphatase and its bone isoenzyme levels between a group receiving lithium and a control group. In this study increased bone isoenzyme of alkaline phosphatase activity above the normal range was found in 27 of 41 patients treated with lithium carbonate. In 19 of 41 patients treated with lithium the activity of bone isoenzyme was increased above the normal range even in the absence of increased activity of serum total alkaline phosphatase.
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PMID:Alterations in human serum alkaline phosphatase and its bone isoenzyme by chronic administration of lithium. 643 70

Chicken skeletal alkaline phosphatase is subject to competitive inhibitions by vanadate (Ki = 0.38 mM in carbonate, Ki = 0.08 mM in Tris, both at pH 7.4) and phenylphosphonate (Ki = 15 mM in carbonate, Ki = 1.3 mM in Tris, both at pH 7.4), and uncompetitive inhibition by levamisole (Ki = 0.08 mM in carbonate, Ki = 0.10 mM in Tris, both at pH 7.4). The competitive inhibitors were more effective in Tris buffer because nonreactive ternary complexes were formed between alkaline phosphatase, the inhibitor and Tris. The effects of vanadate, phenylphosphonate and levamisole on the proliferation of embryonic chick calvarial cells in vitro were biphasic. Low doses of each agent stimulated 3H-thymidine incorporation into TCA-insoluble material; higher doses were inhibitory. Neither effect could be attributed to inhibition of alkaline phosphatase activity (e.g. 20 microM vanadate should inhibit alkaline phosphatase by 3% but stimulated cell proliferation by 187%; 50 microM vanadate should inhibit alkaline phosphatase by 7% but inhibited 3H-thymidine incorporation by 90%). None of the alkaline phosphatase inhibitors tested affected the cellular concentration of the enzyme during the 24-hour incubation. These studies indicate that alkaline phosphatase inhibitors can have nonspecific effects on bone cells in culture, and that for cells in the osteoblast cell line, an inhibition of alkaline phosphatase activity is not consistently related to a decrease in cell proliferation.
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PMID:Effect of skeletal alkaline phosphatase inhibitors on bone cell proliferation in vitro. 692 63


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