QUANTITATIVE STUDIES ON ISOLATED PANCREATIC ISLETS OF MAMMALS: ENZYMIC HYDROLYSIS OF NUCLEOSIDE DIPHOSPHATES AND p-NITROPHENYL PHOSPHATE IN NORMAL AND CORTISONE-TREATED RATS

1966 ◽  
Vol 36 (2) ◽  
pp. 115-NP ◽  
Author(s):  
I.-B. TÄLJEDAL ◽  
B. HELLMAN ◽  
C. HELLERSTRÖM
Keyword(s):  
Enzyme Activity ◽  
Acid Phosphatase ◽  
Phosphatase Activity ◽  
Sodium Fluoride ◽  
Acid Phosphatase Activity ◽  
Staining Intensity ◽  
Histochemical Staining ◽  
Enzymic Hydrolysis ◽  
Isolated Pancreatic Islets ◽  
Hydrolysis Of

SUMMARY Chemical micromethods and histochemical staining were employed for studies of the enzymic hydrolysis of inosine diphosphate (IDP) and adenosine diphosphate (ADP) and the non-specific acid phosphatase activity of the endocrine pancreas from normal and cortisone-treated rats. The following observations were made: 1. Enzymic dephosphorylation of IDP and ADP was maximal at about pH 8·0. Magnesium and manganese ions enhanced the phosphate liberation, the hydrolysis of ADP being more activated than that of IDP. A marked inhibition of enzyme activity towards either substrate was produced by sodium fluoride, sodium cyanide and ethylene-diaminotetraacetate. Acid phosphatase activity was maximal at about pH 5·5, a tendency for a second activity optimum was noted at about pH 4·0. Acid phosphatase activity was markedly inhibited by sodium fluoride, tartaric acid and formaldehyde. 2. Histochemical staining revealed marked enzyme activity towards IDP and ADP in the capillaries and walls of the large blood vessels throughout the pancreas, whereas the islet cells displayed a moderate reaction. The staining intensity was the same with IDP as with ADP. 3. Cortisone administration reduced the rate of cleavage of both IDP and ADP in both the endocrine and the exocrine pancreas, but the enzymic splitting of these substrates remained unchanged in the liver. Acid phosphatase activity was not influenced in any of these tissues by the steroid treatment.

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.

Acid phosphatase, alkaline phosphatase, and nitrate reductase activity of selected ectomycorrhizal fungi

1989 ◽  
Vol 67 (3) ◽  
pp. 750-753 ◽  
Author(s):  
Iwan Ho
Keyword(s):  
Alkaline Phosphatase ◽  
Enzyme Activity ◽  
Acid Phosphatase ◽  
Nitrate Reductase ◽  
Phosphatase Activity ◽  
Ectomycorrhizal Fungi ◽  
Acid Phosphatase Activity ◽  
Nitrate Reductase Activity ◽  
Reductase Activity ◽  
Phosphatase Alkaline

Seventeen isolates, encompassing five genera and eight species of ectomycorrhizal fungi, were compared for acid phosphatase, alkaline phosphatase, and nitrate reductase activity. Isolates within species differed in enzyme activity and isozyme patterns by host specificity and site (as exemplified by the genus Suillus). Host and site may have affected phosphatase enzyme activity. Generally, the Douglas-fir associates, which dominate in mesic sites, have higher acid phosphatase activity than pine associates, which mostly occupy xeric sites; however, pine associates from mesic sites also have higher acid phosphatase activity (e.g., S. tomentosus). In four isolates of Amanita muscaria, the effect of site was also apparent. Two of them, which have significantly higher acid phosphatase activity than the others, were isolated from mesic sites. The isozyme pattern of the genus Suillus appeared to be separated by host groups. Other isolates with only one species also differed more or less by host groups. They shared at least one band within host groups, except for the two isolates of Paxillus involutus from different hosts. The P. involutus S-403 isolated from an orchard showed much higher nitrate reductase activity than all other isolates. No apparent differences in nitrate reductase activity were found between the other isolates.

scholarly journals Croatian produced unifloral honey characterized according to the protein and proline content and enzyme activities

2016 ◽  
Vol 60 (1) ◽  
pp. 39-48 ◽  
Author(s):  
Ivana Flanjak ◽  
Ivica Strelec ◽  
Daniela Kenjerić ◽  
Ljiljana Primorac
Keyword(s):  
Enzyme Activity ◽  
Acid Phosphatase ◽  
Protein Content ◽  
Glucose Oxidase ◽  
Phosphatase Activity ◽  
Enzyme Activities ◽  
Acid Phosphatase Activity ◽  
Black Locust ◽  
Proline Content ◽  
A Minor

Abstract In honey, the content of proteins, including the enzymes, is relatively low and has a minor nutritive significance. On the other hand, the proteins, including the enzymes, are usually used as honey quality evaluation parameters. This is because protein content and enzyme activities vary regarding the botanical origin of the honey. Since the results of protein content, glucose-oxidase, and acid phosphatase, for honeys produced in Croatia, are not available, four of the most abundant honey types produced in Croatia (black locust, sage, chestnut, and honeydew honey) are characterised according to the protein and proline content and enzyme activities. The characterisation was done to determine specificities and contribute to the characterisation of unifloral honeys. Dark honey types (honeydew and chestnut honey) had a higher proline content, and diastase, invertase, and glucose-oxidase activity than lighter sage and black locust honey. Black locust honey has a naturally low enzyme activity and showed the highest acid phosphatase activity among the analysed honey types, while honeydew honey, otherwise known to possess high proline content and enzyme activity, had a low protein content comparable to black locust honey. Statistically significant correlations were obtained between all analysed parameters, with the exception of acid phosphatase activity.

scholarly journals Canine Filarial Infections in a HumanBrugia malayiEndemic Area of India

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Reghu Ravindran ◽  
Sincy Varghese ◽  
Suresh N. Nair ◽  
Vimalkumar M. Balan ◽  
Bindu Lakshmanan ◽  
...  
Keyword(s):  
Acid Phosphatase ◽  
Phosphatase Activity ◽  
Acid Phosphatase Activity ◽  
Brugia Malayi ◽  
Histochemical Staining ◽  
Molecular Techniques ◽  
High Prevalence ◽  
Acanthocheilonema Reconditum ◽  
Kerala State ◽  
Very High

A very high prevalence of microfilaremia of 42.68 per cent out of 164 canine blood samples examined was observed in Cherthala (of Alappuzha district of Kerala state), a known humanBrugia malayiendemic area of south India. The species of canine microfilariae were identified asDirofilaria repens, Brugia malayi, andAcanthocheilonema reconditum.D. repenswas the most commonly detected species followed byB. pahangi.D. immitiswas not detected in any of the samples examined. Based on molecular techniques, microfilariae with histochemical staining pattern of “local staining at anal pore and diffuse staining at central body” was identified asD. repensin addition to those showing acid phosphatase activity only at the anal pore. Even thoughB. malayilike acid phosphatase activity was observed in few dogs examined, they were identified as genetically closer toB. pahangi. Hence, the possibility of dogs acting as reservoirs of humanB. malayiin this area was ruled out.

scholarly journals PURIFICATION OF GLUTARALDEHYDE ITS SIGNIFICANCE FOR PRESERVATION OF ACID PHOSPHATASE ACTIVITY

1968 ◽  
Vol 16 (3) ◽  
pp. 199-204 ◽  
Author(s):  
H. DARIUSH FAHIMI ◽  
PIERRE DROCHMANS ◽  
A. POPOWSKI
Keyword(s):  
Enzyme Activity ◽  
Acid Phosphatase ◽  
Enzymatic Activity ◽  
Phosphatase Activity ◽  
Rat Liver ◽  
Acid Phosphatase Activity ◽  
High Concentration ◽  
Liver Homogenates ◽  
Inorganic Phosphates

The inhibition of acid phosphatase activity in rat liver homogenates after fixation in different lots of commercial glutaraldehyde is determined and compared with the inhibition following fixation with a distilled product. It is shown that commercial glutaraldehydes inhibit more of the enzyme activity than the distilled product. The acidic products of oxidation of glutaraldehyde do not increase the inhibition of the enzymatic activity. The presence of high concentration of inorganic phosphates in different lots of commercial glutaraldehyde, as presented here, suggests that probably such impurities may be responsible for increased inhibition of phosphatase activity noted after fixation in commercial glutaraldehydes.

Acid phosphatase activity in maize (Zea mays La) seedlings treated with sodium humate

2014 ◽  
Vol 55 (2) ◽  
pp. 181-188 ◽  
Author(s):  
Marie Kummerova ◽  
Vladimir Tichy
Keyword(s):  
Zea Mays ◽  
Enzyme Activity ◽  
Free Radicals ◽  
Acid Phosphatase ◽  
Phosphatase Activity ◽  
Acid Phosphatase Activity ◽  
Sodium Humate ◽  
Humus Substances ◽  
Unfavourable Effect ◽  
Fraction I

Sodium humate increased the acid phosphatase activity of fraction II of imbibing maize caryopses and suppressed the enzyme activity in fraction I. Removal of the testa changed the stimulating action of humate on the acid phosphatase activity of fraction II into an inhibiting one and intensified its unfavourable effect on this enzyme's activity in fraction l. Sodium humate inhibited the acid phosphatase activity of this fraction from both leaves and roots. The results obtained are in agreement with the theory of free radicals of humus substances being involved in action on biuecmbranes.

Localisation cytochimique des activités phosphatasiques acides de champignons mycorhiziens développés sur milieu complet ou carencé en phosphate

1983 ◽  
Vol 61 (5) ◽  
pp. 1411-1414 ◽  
Author(s):  
Bernadette Lacaze
Keyword(s):  
Electron Microscopy ◽  
Enzyme Activity ◽  
Acid Phosphatase ◽  
Phosphatase Activity ◽  
Cell Walls ◽  
Acid Phosphatase Activity ◽  
Inorganic Phosphate ◽  
Light And Electron Microscopy ◽  
Reaction Products ◽  
Cytochemical Study

The mycelia of three mycorrhizal basidiomycètes (Pisolithus tinctorius (Pers.) Coker et Couch., Suillus granulatus (L. ex Fr.) O. Kuntze and S. bellinii (Izenga) Watling) were grown on media with or without inorganic phosphate. A cytochemical study of the distribution of acid phosphatase activity was made using light and electron microscopy. Highly enhanced enzyme activity was observed in the phosphorus-deficient mycelia. Precipitates were located primarily at the surface of the fungal cells. Cell walls appear devoid of reaction products in most cases.

scholarly journals The effect of water and salt stresses on the phosphorus content and acid phosphatase activity in oilseed rape

2014 ◽  
Vol 58 (1) ◽  
pp. 47-57 ◽  
Author(s):  
Stanisław Flasiński ◽  
Ryszard Zamorski ◽  
Urszula Kotowska
Keyword(s):  
Enzyme Activity ◽  
Salt Stress ◽  
Acid Phosphatase ◽  
Water Stress ◽  
Plant Growth ◽  
Phosphatase Activity ◽  
Oilseed Rape ◽  
Acid Phosphatase Activity ◽  
Phosphorus Content ◽  
Young Leaves

Oilseed rape plants responded to water and salt stresses (-0.5 MPa, PEG 6000 and NaCI) by reduction of the fresh and dry weights of shoots and roots. When PEG was used, the ratio of dry weights of roots:shoots surpassed that of controls. The leaf protein content increased considerably. The phosphorus content decreased only in the roots, most significantly after three days of stress. Immediately after the stresses were induced, an increase in the acid phosphatase (AP) activity was noted. Water and salt stresses caused four- and two-fold increases in AP activity in leaves, respectively. Changes in the enzyme activity were negligible in stems and roots. There are nine forms of AP in young leaves of oilseed rape. In the stressed plants, from No. 5 revealed lower activity and forms Nos 8 and 9, higher activities than in the control. The increase in AP activity was directly accompanied by the decrease in the water potential of the tissues. Oilseed rape is considerably less sensitive to salt stress than to water stress, which is manifested as the lower inhibition of plant growth and also by a smaller increase in acid phosphatase activity.

QUANTITATIVE STUDIES ON ISOLATED PANCREATIC ISLETS OF MAMMALS

1964 ◽  
Vol 45 (3) ◽  
pp. 476-486 ◽  
Author(s):  
Claes Hellerström ◽  
Inge-Bert Täljedal ◽  
Bo Hellman
Keyword(s):  
Acid Phosphatase ◽  
B Cells ◽  
Pancreatic Islets ◽  
Phosphatase Activity ◽  
Acid Phosphatase Activity ◽  
List Type ◽  
Acid Phosphatases ◽  
Isolated Pancreatic Islets ◽  
Quantitative Studies ◽  
Tissue Homogenates

ABSTRACT Quantitative studies of non-specific acid phosphatases were performed on isolated pancreatic islets from obese-hyperglycaemic mice. The islets of these animals are composed of a rather pure population of B cells. The following observations were made: Acid phosphatases originating in the islet tissue, showed maximal enzyme activities at about pH 3.5 and 5.3 using p-nitrophenyl phosphate as substrate. The acid phosphatase activity of the exocrine tissue showed a single distinct maximum at about pH 5.3. The islet acid phosphatases were inhibited by sodium fluoride, sodium tartrate and formaldehyde. They were stable against storage in crude tissue homogenates at + 4° C and + 20° C for 48 hours. The pancreatic islets exhibited a significantly higher acid phosphatase activity than the exocrine parenchyma. Starvation for 7 days did not alter the enzyme levels in the islets or acini when measured at pH 5.3, while a probably increased enzyme activity was obtained in both these regions at pH 3.5. There was no evidence for a relationship between the insulin secretion and the acid phosphatase activity of the B cells.

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