Acid phosphatase activity demonstrated by intact Angiostrongylus cantonensis with special reference to its function

Parasitology ◽  
1979 ◽  
Vol 79 (3) ◽  
pp. 417-423 ◽  
Author(s):  
Jun Maki ◽  
Toshio Yanagisawa
Keyword(s):  
Acid Phosphatase ◽  
External Medium ◽  
Reciprocal Inhibition ◽  
Angiostrongylus Cantonensis ◽  
Phosphate Esters ◽  
Glucose Phosphate ◽  
Nitrophenyl Phosphate ◽  
Inhibition Studies ◽  
Hydrolysis Of

SUMMARYIntact Angiostrongylus cantonensis is able to hydrolyse glucose-phosphate esters, mononucleotides and p-nitrophenyl phosphate as well as β-glycerophosphate in vitro. Reciprocal inhibition studies suggest that the hydrolysis of such substrates is due to a non-specific phosphomonoesterase. Molybdate ions, which exert no effect on either the uptake of glucose or the production of lactate, inhibit the hydrolysis of glucose-1- phosphate in the external medium and simultaneously lower the production of lactate by the intact worms in vitro.

scholarly journals Phosphatase synthesis in Klebsiella (Aerobacter) aerogenes growing in continuous culture

1972 ◽  
Vol 127 (1) ◽  
pp. 87-96 ◽  
Author(s):  
P. G. Bolton ◽  
A. C. R. Dean
Keyword(s):  
Alkaline Phosphatase ◽  
Acid Phosphatase ◽  
Continuous Culture ◽  
Activity Profile ◽  
Glucose Effect ◽  
Ph Values ◽  
Nitrophenyl Phosphate ◽  
Wide Range ◽  
Rate Of Hydrolysis ◽  
Hydrolysis Of

1. Phosphatase synthesis was studied in Klebsiella aerogenes grown in a wide range of continuous-culture systems. 2. Maximum acid phosphatase synthesis was associated with nutrient-limited, particularly carbohydrate-limited, growth at a relatively low rate, glucose-limited cells exhibiting the highest activity. Compared with glucose as the carbon-limiting growth material, other sugars not only altered the activity but also changed the pH–activity profile of the enzyme(s). 3. The affinity of the acid phosphatase in glucose-limited cells towards p-nitrophenyl phosphate (Km 0.25–0.43mm) was similar to that of staphylococcal acid phosphatase but was ten times greater than that of the Escherichia coli enzyme. 4. PO43−-limitation derepressed alkaline phosphatase synthesis but the amounts of activity were largely independent of the carbon source used for growth. 5. The enzymes were further differentiated by the effect of adding inhibitors (F−, PO43−) and sugars to the reaction mixture during the assays. In particular, it was shown that adding glucose, but not other sugars, stimulated the rate of hydrolysis of p-nitrophenyl phosphate by the acid phosphatase in carbohydrate-limited cells at low pH values (<4.6) but inhibited it at high pH values (>4.6). Alkaline phosphatase activity was unaffected. 6. The function of phosphatases in general is discussed and possible mechanisms for the glucose effect are outlined.

Polyphosphate body and acid phosphatase localization in Nostoc sp.

1984 ◽  
Vol 30 (1) ◽  
pp. 8-15 ◽  
Author(s):  
John D. DuBois ◽  
Keith R. Roberts ◽  
Lawrence A. Kapustka
Keyword(s):  
Enzyme Activity ◽  
Acid Phosphatase ◽  
Phosphatase Activity ◽  
Acid Phosphatase Activity ◽  
Energy Stress ◽  
Nitrophenyl Phosphate ◽  
Carbon Compounds ◽  
Electron And Light Microscopy ◽  
Polyphosphate Bodies ◽  
Hydrolysis Of

Polyphosphate bodies and acid phosphatase activity were characterized in Nostoc sp. to determine if the hydrolysis of polyphosphate bodies occurs during dark (energy stress) periods. Electron and light microscopy were used to locate polyphosphate bodies. Acid phosphatase activity was measured using p-nitrophenyl phosphate as the substrate to determine net changes in the level of the enzyme activity. To induce energy stress, Nostoc sp. cells were kept in the dark for 72 h to deplete stored carbon compounds. Cells incubated in the light for 72 h (controls) showed acid phosphatase activity localized around the perimeter of polyphosphate bodies. When cells were incubated in the dark, acid phosphatase activity occurred throughout the polyphosphate body matrix. However, complete hydrolysis of the polyphosphate body did not occur and the rate of acid phosphatase activity was not affected.

scholarly journals Alloxan cytotoxicity in vitro. Inhibition of rubidium ion pumping in pancreatic β-cells

1977 ◽  
Vol 162 (1) ◽  
pp. 9-18 ◽  
Author(s):  
L Å Idahl ◽  
Å Lernmark ◽  
J Sehlin ◽  
I B Täljedal
Keyword(s):  
Plasma Membranes ◽  
Islet Cells ◽  
Protective Action ◽  
Inhibitory Effect ◽  
Dependent Manner ◽  
Nitrophenyl Phosphate ◽  
Cation Pump ◽  
Ion Pumping ◽  
Hydrolysis Of

Exposing micro-dissected pancreatic islets of non-inbred ob/ob mice to 2-5 mM-alloxan for 10 min decreased the ability of the islets to accumulate Rb+. Rb+ accumulation in pieces of exocrine pancreas was unaffected by alloxan. When islets were treated with alloxan in the presence of 2-20 mM-D-glucose, the Rb+-accumulating ability was protected in a dose-dependent manner. The protective action of D-glucose was reproduced with 3-O-methyl-D-glucose but not with L-glucose or D-mannoheptulose; mannoheptulose prevented D-glucose from exerting its protective action. The inhibition of Rb+ accumulation was due to a decreased inward pumping, since alloxan did not affect Rb+ efflux from pre-loaded islets. The inhibitory effect of alloxan had a latency of about 1 min, as revealed by experiments with dispersed islet cells in suspension. Alloxan-treated islets showed only a marginal decrease in ATP and no change in glucose 6-phosphate concentration. Although alloxan slightly decreased the hydrolysis of ATP in a subcellular fraction enriched in plasma membranes, this effect could not be attributed to a ouabain-sensitive adenosine triphosphatase. The plasma membranes exhibited a K+-activated hydrolysis of p-nitrophenyl phosphate; this enzyme activity too was insensitive to alloxan. Glucose may protect the univalent-cation pump by preventing permeation of alloxan via a path coupled to the hexose-transport system. Inhibition of the pump may be fundamental to the induction of alloxan-diabetes.

Malathion-specific resistance in a strain of the rust red grain beetle Cryptolestes ferrugineus (Coleoptera: Cucujidae)

1998 ◽  
Vol 88 (2) ◽  
pp. 199-206 ◽  
Author(s):  
A.G. Spencer ◽  
N.R. Price ◽  
A. Callaghan
Keyword(s):  
Resistant Strain ◽  
Specific Resistance ◽  
Strain Differences ◽  
Gas Chromatography Mass Spectrometry ◽  
Cryptolestes Ferrugineus ◽  
Tributyl Phosphorotrithioate ◽  
Inhibition Studies ◽  
Hydrolysis Of ◽  
Naphthyl Acetate

AbstractA strain of Cryptolestes ferrugineus (Stephens) bred for malathion-specific resistance was found to be 650 fold resistant at LD50 when compared with a susceptible strain bred from the same stock. Resistance was more than 98% synergized by triphenyl phosphate and S,S,S-tributyl phosphorotrithioate, but unaffected by piperonyl butoxide. AChE inhibition by malaoxon varied slightly between the strains. Non-specific esterase activity as measured by the hydrolysis of α-naphthyl acetate was slightly reduced in the resistant strain whereas there were no inter-strain differences in the hydrolysis of β-naphthyl acetate. Products of in vitro metabolism of malathion were identified by thin-layer chromatography and gas chromatography-mass spectrometry as α- and β-malathion mono-acids. It was therefore concluded that resistance was due to the hydrolytic breakdown of malathion by a malathion-specific carboxylesterase. The rate of in vitro malathion hydrolysis was found to be 31 times greater in the resistant strain. In vitro inhibition studies indicated that resistance is attributable to a carboxylesterase unique to the resistant strain. The implications of these results are discussed in relation to work recently carried out on malathion-specific resistance in dipterous species.

scholarly journals Subcellular localization and tissue distribution of sialic acid-forming enzymes. N-acetylneuraminate-9-phosphate synthase and N-acetylneuraminate 9-phosphatase

1984 ◽  
Vol 223 (2) ◽  
pp. 323-328 ◽  
Author(s):  
J Van Rinsum ◽  
W Van Dijk ◽  
G J Hooghwinkel ◽  
W Ferwerda
Keyword(s):  
Subcellular Localization ◽  
Biosynthetic Pathway ◽  
Cytosolic Fraction ◽  
Phosphate Esters ◽  
Rat Tissues ◽  
Acetylneuraminic Acid ◽  
Nitrophenyl Phosphate ◽  
Sucrose Medium ◽  
Hydrolysis Of ◽  
Phosphate Synthase

The activities of N-acetylneuraminate 9-phosphate synthase and N-acetylneuraminate 9-phosphatase, the two enzymes involved in the final steps of the biosynthetic pathway of N-acetylneuraminic acid, were measured with the substrates N-acetyl[14C]mannosamine 6-phosphate and N-acetyl[14C]neuraminic acid 9-phosphate respectively. Subcellular localization studies in rat liver indicated that both enzymes are localized in the cytosolic fraction after homogenization in sucrose medium. To test the possibility of misinterpretation due to the hydrolysis of N-acetylneuraminic acid 9-phosphate by non-specific phosphatases, the hydrolysis of various phosphate esters by the cytosolic fraction was tested. Only p-nitrophenyl phosphate was hydrolysed; however, competition studies with N-acetylneuraminic acid 9-phosphate and p-nitrophenyl phosphate indicated that two different enzymes were involved and that no competition existed between the two substrates. In various other rat tissues N-acetylneuraminate-9-phosphate synthase and N-acetylneuraminate 9-phosphatase activities were detected, suggesting that N-acetylmannosamine 6-phosphate is a general precursor for N-acetylneuraminic acid biosynthesis in all the tissues studied.

Alkaline phosphatases of Neurospora crassa. Part II product inhibition studies

1972 ◽  
Vol 18 (4) ◽  
pp. 407-421 ◽  
Author(s):  
F. W. J. Davis ◽  
Howard Lees
Keyword(s):  
Neurospora Crassa ◽  
Competitive Inhibitor ◽  
Product Inhibition ◽  
Nitrophenyl Phosphate ◽  
Wide Range ◽  
Phosphate Hydrolysis ◽  
Non Linear ◽  
Inhibition Studies ◽  
Enzyme Complexes ◽  
Hydrolysis Of

A partially purified preparation of the constitutive alkaline phosphatase from Neurospora crassa, containing two electrophoretically distinct activities was used in initial studies of product inhibition patterns. Inorganic phosphate was shown to be a linear competitive inhibitor, and p-nitrophenol to be a non-linear, non-competitive inhibitor of p-nitrophenyl phosphate hydrolysis. Glycerol was shown to be a linear non-competitive inhibitor of β-glycerophosphate hydrolysis.A purification procedure whereby one enzyme activity could be obtained free of the second was devised. The purified enzyme catalyzed the hydrolysis of a wide range of substrates and had a molecular weight of 111 000. Its hydrolysis of glucose 6-phosphate was competitively inhibited by phosphate and non-competitively inhibited by glucose. Both inhibitions were linear. Hydrolysis of p-nitrophenyl phosphate was competitively inhibited by phosphate in a linear manner, but p-nitrophenol was a non-linear, non-competitive inhibitor. Alternate product inhibition by glucose was linear competitive. No inhibition by p-nitrophenol of glucose 6-phosphate hydrolysis could be detected.The inhibition data for glucose 6-phosphate and β-glycerophosphate may be consistent with an ordered Uni-Bi mechanism expanded to include one or more isomerizations of enzyme complexes. The postulation of a different mechanism involving alternate pathways is probably required to explain the data obtained when p-nitrophenyl phosphate was the substrate.

Biochemical properties of tartrate-resistant acid phosphatase in serum of adults and children.

1978 ◽  
Vol 24 (7) ◽  
pp. 1105-1108 ◽  
Author(s):  
W K Lam ◽  
D T Eastlund ◽  
C Y Li ◽  
L T Yam
Keyword(s):  
Acid Phosphatase ◽  
Catalytic Properties ◽  
Biochemical Properties ◽  
Tartrate Resistant Acid Phosphatase ◽  
Total Acid ◽  
Average Value ◽  
Nitrophenyl Phosphate ◽  
Adults And Children ◽  
Major Acid ◽  
Hydrolysis Of

Abstract Spectrophotometry of total acid phosphatase activity in children's sera showed an average value of 22.4 +/- 2.9 and 7.4 +/- 0.8 U/liter, for the hydrolysis of p-nitrophenyl phosphate and alpha-naphthyl phosphate, respectively. Analyses of "band 5b", after electrophoresis on acrylamide gel, gave even higher values. The values for children's sera were much higher than those for sera from adults. The multiplicity of acid phosphatases in sera of children and adults was studied by electrophoresis on acrylamide gel and by chromatography on CM-Sepharose. Both methods showed the major acid phosphatase in children's sera to be an acid pyrophosphatase, band 5b. Its catalytic properties are indistinguishable from the enzyme previously isolated from the spleen of leukemic reticuloendotheliosis.

THE WHEAT LEAF PHOSPHATASES: VII. FURTHER STUDIES ON INHIBITORS AT pH 5.7

1963 ◽  
Vol 41 (1) ◽  
pp. 1727-1731 ◽  
Author(s):  
D. W. A. Roberts
Keyword(s):  
Acid Phosphatase ◽  
Enzymatic Hydrolysis ◽  
Inhibitory Effect ◽  
Substrate Specificities ◽  
Nitrophenyl Phosphate ◽  
Wheat Leaf ◽  
Hydrolysis Of

A survey of the inhibitory effect of various ribonucleosides, deoxyribonucleosides, sugars, phenols, and vitamins on the hydrolysis of 17 phosphatase substrates has been made. The more soluble ribonucleosides and deoxyribonucleosides inhibited the enzymatic hydrolysis of adenosine 5′-phosphate, phenolphthalein diphosphate, phenylphosphate, p-nitrophenyl phosphate, and in some cases the hydrolysis of adenosine 3′-phosphate, adenosine 2′-phosphate, and riboflavin 5′-phosphate. A 0.02 M concentration of orthophosphate inhibited the hydrolysis of all the compounds tested except adenosine 5′-phosphate and phenolphthalein diphosphate.These results, together with earlier findings, are discussed in terms of the concept that wheat leaf press juice contains two types of acid phosphatase, namely, β-glycerophosphatase and adenosine 5′-phosphatase. These two types of enzyme appear to have partially overlapping substrate specificities.

scholarly journals Presence of multiple acid phosphatases activity in seedlings of cucumber, radish and rocket salad

2008 ◽  
Vol 38 (3) ◽  
pp. 650-657 ◽  
Author(s):  
Luciane Almeri Tabaldi ◽  
Raquel Ruppenthal ◽  
Luciane Belmonte Pereira ◽  
Denise Cargnelutti ◽  
Jamile Fabbrin Gonçalves ◽  
...  
Keyword(s):  
Acid Phosphatase ◽  
Phosphate Esters ◽  
Acid Phosphatases ◽  
Simple Preparation ◽  
Toxicological Studies ◽  
Plant Enzymes ◽  
Optimum Ph ◽  
Ph Range ◽  
Hydrolysis Of ◽  
Assay Conditions

Acid phosphatases (3.1.3.2) are a group of enzymes widely distributed in nature, which catalyze the hydrolysis of a variety of phosphate esters in the pH range of 4-6. We confirmed the presence of acid phosphatases in seedlings of cucumber (Cucumis sativus), radish (Raphanus sativus) and rocket salad (Eruca vesicaria) under different assay conditions using a rapid and simple preparation. The results showed that the optimum pH and temperature used for all species were close to 5.5 and 35°C, respectively. The enzyme was inhibited by molybdate, fluoride, azide, levamisole, orthovanadate, Zn2+ and Cu2+. Suramin had no effect on enzyme activity. The acid phosphatase from cucumber, radish and rocket salad hydrolyzed a wide variety of phosphate esters and the highest activity was observed with PPi, ATP and GTP. These results demonstrate that the enzyme investigated in this study is different from well known ester phosphate cleaving plant enzymes (apyrase and inorganic pyrophosphatases) and this preparation could be a useful tool to future toxicological studies and to study initially all isoforms of acid phosphatase.

Bovine milk acid phosphatase: II. Binding to casein substrates and heat-inactivation studies

1974 ◽  
Vol 41 (2) ◽  
pp. 229-237 ◽  
Author(s):  
A. T. Andrews
Keyword(s):  
Acid Phosphatase ◽  
Protein Denaturation ◽  
Bovine Milk ◽  
Raw Milk ◽  
Heat Inactivation ◽  
Heat Stable ◽  
First Order Kinetics ◽  
Nitrophenyl Phosphate ◽  
Substrate Protection ◽  
Hydrolysis Of

SummaryThe acid phosphatase of bovine milk was further purified to yield enzyme with an activity of about 2 units/mg. This was almost 105 times the activity present in milk and enabled a detailed study of heat inactivation to be made, together with further measurements on binding to casein substrates.The effectiveness of caseins as inhibitors of the hydrolysis of p-nitrophenyl phosphate by acid phosphatase paralleled the phosphate content of the casein molecules, so that αs1-casein A was a more potent inhibitor with a K1 of 1·7 mM than β-casein A1A2 (K1 = 4·3 mM), which in turn was more inhibitory than κ-casein A (K1 = 5·9 mM).The heat inactivation of acid phosphatase followed first-order kinetics at pH 4·9, 5·2 and 6·7 and values of E, the activation energy, were between 2·4×105 and 3·0×105 J mole −1 in all cases, consistent with simple protein denaturation. The presence of 1% αs1-casein A, 1% β-casein A1A2, 1% κ-casein A, 1% isoelectrically precipitated ‘whole’ casein and 1% fresh raw milk provided no substrate protection at pH 5·2 or 6·7. Acid phosphatase was somewhat less heat stable at pH 6·7 than at pH 4·9, but may be expected to survive typical milk pasteurization conditions almost completely. However, conventional milk sterilization or ultra-high-temperature (UHT) processes would be expected to give total inactivation.

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