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 purpose of this investigation was to establish the properties of [3H]dexamethasone binding sites in cytosol of human placenta at term. Cytosol containing 20 mM sodium molybdate (MoO4Na2) was incubated for 120 min at 20 degrees C with 40 nM [3H]dexamethasone. The following properties were observed: (a) a single population of binding sites of high affinity and low capacity was measured by Scatchard analysis; (b) potent glucocorticoids such as dexamethasone and cortisol displaced the tritiated ligand, progesterone showed an intermediate activity, whereas cortisone, testosterone and 17 beta-estradiol were ineffective competitors; (c) ultracentrifugation on 16-41% glycerol gradients containing 20 mM MoO4Na2 yielded sedimentation values of 10.25 +/- 0.35 S (n = 4 placentas); (d) the binding sites could be differentiated from the enzyme 11 beta-hydroxysteroid dehydrogenase, as the activity of the former, but not that of the latter, was greatly dependent on the presence of MoO4Na2 in the incubation medium. Inactivation of binding sites labelled with [3H]dexamethasone by incubation at 20 degrees C was prevented by phosphatase inhibitors such as 20 mM MoO4Na2 (P less than 0.01), 20 mM sodium tungstate (WO4Na2) (P less than 0.01) and to a lower extent by 5 mM ATP and cAMP (P less than 0.05). 50 mM NaF, 5 mM GTP or cGMP had no effect. The protection afforded by MoO4Na2 and WO4Na2 was correlated with a significant inhibition of the activity of acid phosphatase, but not alkaline phosphatase. Neither ATP nor cAMP modified phosphatase activity. It is suggested that binding sites for [3H]dexamethasone in cytosol of human placenta showed properties similar to those described for glucocorticoid receptors in target cells, and that these binding sites are regulated by phosphorylation and dephosphorylation mechanisms.
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PMID:Influence of phosphatase inhibitors and nucleotides on [3H]dexamethasone binding in cytosol of human placenta. 649 96

3-Oxo-5 alpha-steroid: NAD+ delta 4-oxidoreductase ("NADH-5 alpha-reductase", EC 1.3.1.?) is rapidly inactivated in the presence of 17 beta-hydroxy-4-androsten-3-one (testosterone). This activation is prevented by increasing the phosphate concentration. When the enzyme assay is carried out in Tris-HCl, only a small activity (1.7 nmol X min-1 X mg-1) is observed which may be further decreased by addition of phosphatases. Addition of the phosphatase inhibitor dextran sulphate or ATP, Mg++ and c-AMP results in a significant increase of activity (228% and 273%, respectively) compared with the Tris-HCl control. Glycerol 2-phosphate and glycerol 3-phosphate have a stabilizing effect on 3-oxo-5 alpha-steroid: NAD+ delta 4-oxidoreductase by decreasing the Km towards the substrate testosterone from 1.2 X 10(-5) mol/l to 3.3 X 10(-6) mol/l. V remains unchanged. Half maximal velocity (testosterone reduction) is achieved with 20 mumol/l glycerol 2-phosphate and glycerol 3-phosphate. Addition of c-AMP dependent protein kinase (EC 2.7.1.37) to a microsomal preparation pretreated with alkaline phosphatase (EC 3.1.3.1) results in a significant increase of 3-oxo-5 alpha-steroid: NAD+ delta 4-oxidoreductase activity compared with the control.
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PMID:Rat liver 3-oxo-5 alpha-steroid delta 4-dehydrogenase. Modulation of enzyme activity by changes in phosphorylation state. 652 91

The production of the bacteriocin ulceracin 378 by Corynebacterium ulcerans 378 was demonstrated during the growth of the organism on solid medium. Ulceracin 378 was not found in broth cultures and could not be extracted from the organisms by various solvents and salt solutions. Ulceracin 378 was not inducible by UV irradiation or mitomycin C treatments. Ulceracin 378 was active against all of the C. ulcerans strains tested and some related species, but it was not autoinhibitory. The active material was not phage related and was extracted from cultures grown on semisolid media composed of proteose peptone, Tween 80, Casamino Acids, glycerol, and sodium chloride. The yield was significantly reduced by either increasing the agar concentration or omitting Tween 80. Ulceracin 378 was resistant to DNase, RNase, phospholipases C and D, and alkaline phosphatase but was susceptible to proteolytic enzymes. This suggests that the active principle of ulceracin is protein in nature. Ulceracin 378 was partially purified by ammonium sulfate fractionation, dialysis, and chromatography on DEAE-cellulose.
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PMID:Production of a bacteriocin, ulceracin 378, by Corynebacterium ulcerans. 668 39

Growth conditions affect the quantity and distribution of alkaline phosphatase (orthophosphoric-monoester phosphohydrolase (alkaline optimum), EC 3.1.3.1) in Bacillus licheniformis MC14. The soluble alkaline phosphatase, which has been found in biochemical localization studies between the cell wall and cell membrane (Glynn, J.A., Schaffel, S.D., McNicholas, J.M. and Hulett, F.M. (1977) J. Bacteriol. 129, 1010-1019), was localized via electron microscope histochemistry in cells cultured under conditions which result in increased quantities of this activity. This soluble alkaline phosphatase was stabilized with 20% glycerol and purified to homogeneity as determined by sodium dodecyl sulfate(SDS)-polyacrylamide gel electrophoresis. The purified enzyme is soluble in dilute buffer. This soluble alkaline phosphatase has been characterized and compared to the membrane-associated alkaline phosphatase from this organism.
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PMID:A soluble alkaline phosphatase from Bacillus licheniformis MC14. Histochemical localization, purification, characterization and comparison with the membrane-associated alkaline phosphatase. 678 99

The alkaline phosphatase of Plectonema boryanum shows a considerable increase in activity following placement of the cells in a phosphate free medium. Five days of phosphate starvation result in a 14-fold increase of alkaline phosphatase activity. Growth in the presence of inhibitors of transcription and translation indicate that the synthesis of the enzyme is de novo. Orthophosphate causes an immediate inhibition of enzyme activity. Enzyme was extracted from P. boryanum with lysozyme or polymyxin B treatment in order to make comparative studies of cell bound and cell free enzyme. Of several enzyme specific inhibitors tested, mercuric chloride was the most effective. Temperature studies showed that the cell bound enzyme was most active at 40 degrees C while the cell free enzyme was most active at 70 degrees C. The pH optimum was 9 for the cell free enzyme, and 8.8 for the cell bound. The enzyme was tested to determine if it could hydrolyse a number of different organic compounds. It hydrolysed p-nitrophenol phosphate 100%, fructose-6-phosphate 45%, beta-glycerol phosphate 25% and other compounds to a lesser degree. Of seventeen other Cyanobacteria tested for alkaline phosphatase, all were positive, and of these eleven were inducible for the enzyme. Ten of the isolates released some of the enzyme into the culture medium. Michaelis constants for the enzyme were also determined.
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PMID:Physiological aspects of alkaline phosphatase in selected cyanobacteria. 679 13

Lung surfactant, a lipid-protein complex purified from dog lungs, contains a highly active phosphomonoesterase associated with it. This phosphatase is quite specific for the hydrolysis of phosphatidic acid and 1-acyl-2-lysophosphatidic acid. The enzyme possesses many of the characteristics of the microsomal enzyme, phosphatidate phosphohydrolase (EC 3.1.3.4). In addition, we have shown that this enzyme will also convert phosphatidylglycerol phosphate [1-(3-sn-phosphatidyl)-sn-glycerol-1-P] to phosphatidylglycerol [1-(3-sn-phosphatidyl)-sn-glycerol] and Pi. The phosphatidylglycerol phosphate was made available to the surfactant enzyme in a coupled assay by hydrolysis of cardiolipin [1-(3-sn-phosphatidyl)-3-(3-sn-phosphatidyl)-sn-glycerol] by stereospecific cleavage with phospholipase C (phosphatidylcholine cholinephosphohydrolase, EC 3.1.4.3) from Bacillus cereus. This enzyme has been previously shown to generate the naturally occurring isomer of phosphatidylglycerol phosphate because it has specificity for the 3-(3-sn-phosphatidyl) group of cardiolipin. Other properties of the surfactant enzyme are discussed in relation to its presence in lung surface active material.
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PMID:Properties of an acid phosphatase in pulmonary surfactant. 692 79

One of the two forms of DNA polymerase alpha from ovaries of the frog Xenopus laevis catalyzed ribonucleoside triphosphate-dependent DNA synthesis on single-stranded circular fd phage DNA templates. DNA synthesis was dependent on ATP and added template. CTP, GTP, and UTP stimulated DNA synthesis but were not required and could not substitute for ATP. DNA synthesis was not inhibited by alpha-amanitin. Neither poly(dT) nor double-stranded DNA served as template. Analysis of [32P]-dTMP-labeled product by neutral and alkaline agarose gel electrophoresis showed that 0.1- to 1-kilobase DNA fragments (average size of approximately equal to 0.25 kilobase) were synthesized. The fragments were not covalently linked to the template. Either [alpha-32P]NMP, [gamma-32P]ATP, or [gamma-32P]GTP were incorporated also into the product. Analysis of the product after hydrolysis by KOH, alkaline phosphatase, or bacteriophage T4 3' leads to 5' exonuclease showed the presence of a small oligoribonucleotide primer at the 5' end of the newly synthesized DNA. NTP-dependent DNA-synthesizing activity copurified on six columns and cosedimented during glycerol gradient centrifugation with one form of DNA polymerase alpha activity but not with the other form. These results suggest that DNA primase activity is associated with one of the two forms of X. laevis DNA polymerase alpha.
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PMID:DNA primase activity associated with DNA polymerase alpha from Xenopus laevis ovaries. 696 3

Mutants constitutive for the novel outer membrane protein Ic (e or E) contained a recently discovered binding protein for sn-glycerol-3-phosphate. The corresponding parental strains missing the outer membrane protein Ic (e, E) were negative or strongly reduced in the synthesis of the binding protein. In addition, strains that were previously isolated as mutants constitutive for the sn-glycerol-3-phosphate transport system (ugp(+) mutants) and that produced the novel periplasmic proteins GP1 to GP4 also synthesized a new outer membrane protein with the same electrophoretic mobility on sodium dodecyl sulfate-polyacrylamide gels as protein Ic. Screening of different ugp(+) mutants revealed the existence of three types in respect to the four novel periplasmic proteins GP1, -2, -3, and -4: (i) one containing all four proteins; (ii) one containing only proteins GP1, -2, and -3; (iii) one containing only proteins GP1, -2, and -4. In confirmation of the data presented in the accompanying paper by Tommassen and Lugtenberg (J. Bacteriol. 143:151-157, 1980), we found that purified GP1 is identical to alkaline phosphatase, whereas purified GP3 has binding activity of inorganic phosphate and is identical to the phosphate-binding protein. Moreover, growth conditions that lead in a wild-type strain to the derepression of alkaline phosphatase synthesis also derepressed the synthesis of the sn-glycerol-3-phosphate-binding protein as well as the corresponding transport system. Thus, the new sn-glycerol-3-phosphate transport system is part of the alkaline phosphatase regulatory system.
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PMID:Co-regulation in Escherichia coli of a novel transport system for sn-glycerol-3-phosphate and outer membrane protein Ic (e, E) with alkaline phosphatase and phosphate-binding protein. 699 24

The ugp-dependent transport system for sn-glycerol-3-phosphate has been characterized. The system is induced under conditions of phosphate starvation and in mutants that are constitutive for the pho regulon. The system does not operate in membrane vesicles and is highly sensitive toward osmotic shock. The participation of a periplasmic binding protein in the transport process can be deduced from the isolation of transport mutants that lack the binding protein. As with other binding protein-dependent transport systems, this protein appears to be necessary but not sufficient for transport activity. The isolation of mutants has become possible by selection for resistance against the toxic analog 3,4-dihydroxybutyl-1-phosphonate that is transported by the system. sn-Glycerol-3-phosphate transported via ugp cannot be used as the sole carbon source. Strains have been constructed that lack alkaline phosphatase and glycerol kinase. In addition, they are constitutive for the glp regulon and contain high levels of glycerol-3-phosphate dehydrogenase. Despite the fact that these strains exhibit high ugp-dependent transport activity for sn-glycerol-3-phosphate they are unable to grow on it as a sole source of carbon. However, when cells are grown on an alternate carbon source, (14)C label from [(14)C]sn-glycerol-3-phosphate appears in phospholipids as well as in trichloroacetic acid-precipitable material. The incorporation of (14)C label is strongly reduced when sn-glycerol-3-phosphate is the only carbon source. In the presence of an alternate carbon source, this inhibition is relieved, and sn-glycerol-3-phosphate transported by ugp can be used as the sole source of phosphate.
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PMID:Characteristics of a binding protein-dependent transport system for sn-glycerol-3-phosphate in Escherichia coli that is part of the pho regulon. 704 85

The 10 S DNA polymerase alpha from calf thymus (Masaki, S., and Yoshida, S. (1978) Biochim. Biophys. Acta 521, 74-88) has been purified to near homogeneity. The most purified fraction obtained by repeated sucrose rate-zonal centrifugation contained three large polypeptides of 150,000, 145,000, and 140,000 daltons and three to four smaller polypeptides ranging from 43,000 to 50,000 daltons. A good resolution of these polypeptides was achieved on a sodium dodecyl sulfate-polyacrylamide linear gradient gel (5-20%) which was stained by the silver stain method. The three large polypeptides were also observed in the more crude fractions prepared in the presence of three kinds of protease inhibitors. By a peptide mapping analysis, it was revealed that these three polypeptides have a similar primary structure. Treatments of the enzyme with alkaline phosphatase, phosphodiesterase, and neuraminidase did not affect the gel pattern. These results indicate that the 10 S DNA polymerase alpha of calf thymus has a microheterogeneity in terms of the large polypeptide component. Among these three large polypeptides, the two polypeptides of 150,000 and 145,000 daltons disappeared by keeping the sucrose gradient fraction at 4 degrees C in the absence of glycerol, while the 140,000-dalton polypeptide was well preserved. The poly(rA)oligo(dT)-dependent activity of 10 S DNA polymerase alpha was selectively lost under this condition.
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PMID:10 S DNA polymerase alpha of calf thymus shows a microheterogeneity in its large polypeptide component. 708 21


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