Control and localization of the phosphatases in conidia of Neurospora crassa

1989 ◽  
Vol 35 (9) ◽  
pp. 830-835 ◽  
Author(s):  
E. Nahas
Keyword(s):  
Alkaline Phosphatase ◽  
Enzyme Activity ◽  
Neurospora Crassa ◽  
Culture Medium ◽  
Alkaline Phosphatases ◽  
Cell Compartments ◽  
Surface Active Agents ◽  
Cell Enzyme ◽  
A Cell ◽  
Surface Active

Repressible acid, repressible alkaline, and constitutive alkaline phosphatases were studied with respect to their control and localization in conidia of Neurospora crassa. In contrast to constitutive alkaline phosphatase, the production and secretion of repressible phosphatases is regulated by phosphate level and pH of the culture medium. Phosphatase activity increased with conidial germination and was detectable partially in the growth medium after 5 h incubation. These enzymes were found to be located in different cell compartments. Part of the whole cell enzyme activity involved a soluble exoconidial fraction, and another part, a cell-bound enzyme that remained after successive washes. The cell-bound enzyme was sensitive to treatment with dilute acid and was thought to be located in the mural space. A third part of the enzyme activity was judged to be intracellular, as shown by treatments with surface-active agents and heat, which disrupted the conidia or destroyed the conidial permeability barriers. On the basis of these criteria, the constitutive alkaline phosphatase was considered to be more cryptic than the repressible phosphatases. The alkaline phosphatases were also active during heat treatment, suggesting they may be involved in the mechanism of secretion.Key words: Neurospora crassa, repressible acid phosphatase, repressible alkaline phosphatase, constitutive alkaline phosphatase, conidia.

PHOSPHATASE OF RABBIT POLYMORPHONUCLEAR LEUCOCYTES

1949 ◽  
Vol 27e (5) ◽  
pp. 290-307 ◽  
Author(s):  
D. M. Cram ◽  
R. J. Rossiter
Keyword(s):  
Alkaline Phosphatase ◽  
Enzyme Activity ◽  
Acid Phosphatase ◽  
Bile Salts ◽  
Polymorphonuclear Leucocytes ◽  
Alkyl Sulphate ◽  
Low Concentrations ◽  
Activity Curve ◽  
Surface Active ◽  
Active Substances

Rabbit polymorphonuclear leucocytes contain an active phosphatase that readily hydrolyzes disodium phenyl phosphate. The pH activity curve of the enzyme was found to have two maxima, one in the region of pH 10 and the other in the region of pH 5. The alkaline phosphatase was much more active than the acid phosphatase. The concentration of alkaline phosphatase in rabbit white cells was approximately one thousand times that of the enzyme in the serum. Under the conditions of study, the alkaline phosphatase activity was proportional to the concentration of the enzyme. The effect of substrate concentration on the enzyme activity was studied and the Michaelis constant (Ks) determined. An excess of substrate inhibited the enzyme. The course of the reaction was linear with time for the first 60 min.; after 90 min. the activity fell off faster than would be expected if the reaction were of the first order.Magnesium and glycine, in low concentrations, caused an increase in the enzyme activity, whereas zinc, cyanide, borate, phosphate, bile salts, and glycine, in higher concentrations, were inhibitory. Fluoride had no demonstrable effect. Surface-active substances, such as saponin, bile salts, or alkyl sulphate, liberated the enzyme from the cells. Similar results were obtained when α-glycerophosphate or β-glycerophosphate was used as the substrate.The alkaline phosphatase can be considered to belong to Class AI of Folley and Kay (22) and the acid phosphatase to Class AII. The alkaline phosphatase can also be considered to be a Phosphatase II of Cloetens (9).

A comparison of certain isozyme patterns in lobeless and normal embryos of the snail, Ilyanassa obsoleta

Development ◽  
1971 ◽  
Vol 26 (3) ◽  
pp. 339-349
Author(s):  
Sallie B. Freeman
Keyword(s):  
Alkaline Phosphatase ◽  
Enzyme Activity ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Polyacrylamide Gel ◽  
Ilyanassa Obsoleta ◽  
Alkaline Phosphatases ◽  
Polar Lobe ◽  
Specific Nature ◽  
Isozyme Patterns

A study was made of the emergence of certain enzymes during the embryogenesis of Ilyanassa. Lobeless and normal embryos were compared in order to determine the effect of polar lobe removal on subsequent molecular developments. Polyacrylamide gel electrophoresis in capillary tubes, a technique requiring only small numbers of embryos, was used to obtain the isozyme patterns of alkaline phosphatases and of esterases. It was found that lobe removal interfered with the emergence of normal isozyme patterns of alkaline phosphatase and esterase during development. Certain bands of enzyme activity were severely reduced or absent while others appeared to be normal. The results provide further evidence that the influence of the polar lobe on development is of a specific nature.

Biochemical and histochemical studies of alkaline and acid phosphatases in a digenetic trematode,Pegosomum egretti

1986 ◽  
Vol 60 (4) ◽  
pp. 293-298 ◽  
Author(s):  
Indra Rajvanshi ◽  
K. L. Mali
Keyword(s):  
Alkaline Phosphatase ◽  
Enzyme Activity ◽  
Acid Phosphatase ◽  
Raw Materials ◽  
Digenetic Trematode ◽  
Acid Phosphatases ◽  
Alkaline Phosphatases ◽  
Optimum Ph ◽  
Standard Techniques ◽  
Alkaline And Acid Phosphatases

ABSTRACTThe biochemistry and histochemistry ofPegosomum egrettihave been studied using standard techniques. Phosphatases were analysed colorimetrically; the optimum pH for acid phosphatase activity was 5·0 and for alkaline phosphatase was 10·0. The results were compared with those of other trematodes. Histochemical localization of acid and alkaline phosphatases revealed differences in enzyme activity in various tissues. These differences in the site and pattern of distribution of the two enzymes have been discussed in relation to transport of raw materials and the metabolism of the cell concerned.

Yeast Permeabilization as a Tool for Measurment of in situ Enzyme Activity: Localization of Alkaline Phosphatase

1998 ◽  
Vol 53 (5-6) ◽  
pp. 347-351 ◽  
Author(s):  
D. Spasova ◽  
D. Galabova
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Alkaline Phosphatase ◽  
Enzyme Activity ◽  
Yeast Cells ◽  
Ionic Surfactant ◽  
Alkaline Phosphatases ◽  
Permeabilized Cells ◽  
Triton X

Abstract The biochemical and ultracytochemieal localization of alkaline phosphatases in permeabilized cells of Saccharomyces cerevisiae 257 has been studied. The treatment with non-ionic surfactant Triton X-100 allows the penetration of the substrate into intact yeast cells and thus provides detailed detection of the enzyme activity in ultracytochemical studies.

scholarly journals Identification of a Regulated Alkaline Phosphatase, a Cell Surface-Associated Lipoprotein, in Mycobacterium smegmatis

2003 ◽  
Vol 185 (16) ◽  
pp. 4983-4991 ◽  
Author(s):  
Jordan Kriakov ◽  
Sun hee Lee ◽  
William R. Jacobs
Keyword(s):  
Alkaline Phosphatase ◽  
Cell Surface ◽  
Mycobacterium Smegmatis ◽  
Signal Sequence ◽  
Constitutive Expression ◽  
Phosphate Starvation ◽  
Alkaline Phosphatases ◽  
A Cell ◽  
Exported Protein ◽  
Transposon Insertions

ABSTRACT Although alkaline phosphatases are common in a wide variety of bacteria, there has been no prior evidence for alkaline phosphatases in Mycobacterium smegmatis. Here we report that transposon insertions in the pst operon, encoding homologues of an inorganic phosphate transporter, leads to constitutive expression of a protein with alkaline phosphatase activity. DNA sequence analysis revealed that M. smegmatis does indeed have a phoA gene that shows high homology to other phoA genes. The M. smegmatis phoA gene was shown to be induced by phosphate starvation and thus negatively regulated by the pst operon. Interestingly, the putative M. smegmatis PhoA has a hydrophobic N-terminal domain which resembles a lipoprotein signal sequence. The M. smegmatis PhoA was demonstrated to be an exported protein associated with the cell surface. Furthermore, immunoprecipitation of PhoA from [14C]acetate-labeled M. smegmatis cell lysates demonstrated that this phosphatase is a lipoprotein.

Studies on phosphatase systems of cestodes I. Studies on Taenia pisiformis (Cysticercus and adult)

Parasitology ◽  
1957 ◽  
Vol 47 (1-2) ◽  
pp. 70-80 ◽  
Author(s):  
David A. Erasmus
Keyword(s):  
Alkaline Phosphatase ◽  
Enzyme Activity ◽  
Life Cycle ◽  
Acid Phosphatase ◽  
Active Transport ◽  
Relative Magnitude ◽  
Alkaline Phosphatases ◽  
Biochemical Tests ◽  
Acid And Alkaline Phosphatase ◽  
Histochemical Tests

1. The phosphatases present in the adult and cysticercus stages of Taenia pisiformis have been investigated using histochemical and biochemical methods.2. Histochemical tests failed to demonstrate the sites of enzyme activity in the cysticercus.3. In the adult, the acid phosphatase is confined to the cuticle. Alkaline phosphatase occurs in the cuticle, subcuticular cells and the membranes bounding the ovary and vitelline tubules.4. The histochemical distribution is uneven along the length of the worm, both acid and alkaline phosphatase being predominant hi the region of ‘mature’ proglottides. The scolex was negative to both tests.5. Biochemical tests have demonstrated distinct acid and alkaline phosphatases in the cysticercus and adult stages. In the cysticercus the acid enzyme is predominant and in the adult it is the alkaline, implying a change in relative magnitude during the completion of the life cycle.6. pH-activity curves have been obtained for the enzymes of both stages.7. The results are discussed in relation to recent findings in the field of cestode enzymology, and it is suggested that these phosphatases may be associated with active transport of materials across the cuticle and ovarian and vitelline membranes.

Soil response to chemicals used in a field experiment

2013 ◽  
Vol 27 (2) ◽  
pp. 151-158 ◽  
Author(s):  
S. Jezierska-Tys ◽  
A. Rutkowska
Keyword(s):  
Alkaline Phosphatase ◽  
Enzymatic Activity ◽  
Field Experiment ◽  
Soil Microorganisms ◽  
Block Design ◽  
Soil Samples ◽  
Alkaline Phosphatases ◽  
Soil Response ◽  
Negative Effect ◽  
Set Up

Abstract The effect of chemicals (Reglone 200 SL and Elastiq 550 EC) on soil microorganisms and their enzymatic activity was estimated. The study was conducted in a field experiment which was set up in the split-block design and comprised three treatments. Soil samples were taken six times, twice in each year of study. The results showed that the application of chemicals generally had no negative effect on the number of soil microorganisms. The application of Reglone 200 SL caused an increase of proteolytic and ureolytic activity and affected the activity of dehydrogenases, acid and alkaline phosphatases in the soil. The soil subjected of Elastiq 550 EC was characterized by lower activity of dehydrogenases, protease, urease and alkaline phosphatase.

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