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1.
The temperature peak (15 °C) of acid and alkaline phosphatase in this study coincides with a peak in alpha-amylase as seen in an earlier study of roots of Verbascum thapsus. It is speculated that one of the results of higher phosphatase activities may be increased amount of orthophosphate which can be utilized in phosphorylation of soluble carbohydrates which in turn are in greater supply due to the higher activities of the starch-degrading enzymes.A second peak in activities of acid and alkaline phosphatase was seen in plants which were returned to the greenhouse following cold treatment. This increase in enzymatic activities is also similar to increases in activities of three starch degrading enzymes studied earlier. Alkaline phosphatase showed greater activities than did acid phosphatase at lower temperatures (10 and 4 °C) and under greenhouse conditions following cold treatment.  相似文献   

2.
Reduction in alkaline phosphatase activity was observed when HeLa S3 cells were grown in Puck's medium containing high concentrations of human serum. This effect was not seen with the enzyme of Chang liver 8A cells. The induction of increased alkaline phosphatase in HeLa S3 by prednisolone or by osmolality changes was not prevented by serum. The concentration of serum in the culture medium had no influence on acid phosphatase activity.  相似文献   

3.
Synopsis The enzyme histochemistry of the adult rat pineal is reviewed with particular reference to the probable endocrine activity of this organ. The parenchymal cells contain large amounts of oxidative enzymes and non-specific esterase, rather less leucine amino peptidase and acid phosphatase, and only small amounts of phosphorylase and alkaline phosphatase. In addition, high concentrations of alkaline phosphatase are present in the walls of capillary vessels. Leucine aminopeptidase is also seen in the connective tissue around blood vessels.  相似文献   

4.
1. Alkaline phosphatase is covalently bound to bovine mammary microsomal membranes and milk fat globule membranes through linkage to phosphatidylinositol as demonstrated by the release of alkaline phosphatase following treatment with phosphatidylinositol-specific phospholipase C. 2. The release of alkaline phosphatase from the pellet to the supernatant was demonstrated by enzyme assays and electrophoresis. 3. Electrophoresis of the solubilized enzymes showed that the alkaline phosphatase of the microsomal membranes contained several isozymes, while only one band with alkaline phosphatase activity was seen in the fat globule membrane. 4. Levamisole and homoarginine were potent inhibitors of the alkaline phosphatase activities in both membrane preparations and in bovine liver alkaline phosphatase, but not in calf intestinal alkaline phosphatase.  相似文献   

5.
Summary The authors have studied the activity of alkaline and acid phosphatase in the rat and the mouse vaginal anlage. The activity is high in the epithelium of the müllerian vagina and low or uncertain in that of the sinus vagina. When a lumen is formed in the latter, there appears in rat an activity of both phosphatases of the same intensity as seen in the müllerian vagina. In mouse, the epithelium of the müllerian vagina transitory loses its activity of alkaline phosphatase when the epithelium undergoes transformation. The whole vagina is then surrounded by a zone of high stromal activity of alkaline phosphatase. The epithelium lacks activity except in the fornix region where the activity remains in a zone close to the lumen Thereafter the activity disappears in the subepithelial strorna and instead apears in the basal layer of the epithelium. The activity of acid phosphatase increases in the mouse sinus vagina at the same time as lumen is formed, being of the same intensity here as in the müllerian vaginal part.  相似文献   

6.
Abstract. The mode of formation of the molluscan exoskeleton is still poorly understood, but studies on adult snails indicate that enzymes involved in vertebrate bone formation also participate in mollusc shell formation. The enzymes peroxidase, alkaline phosphatase, and acid phosphatase are expressed in a constant pattern and help to identify the different zones of the adult shell-forming tissue. The present study evaluates whether the expression of these enzymes is also a tool for the identification of the developing zones of the embryonic shell-forming tissue. Thus, we analyzed the temporal and spatial activity of the above-mentioned enzymes and of tartrate-resistant acid phosphatase in the shell forming tissues in Biomphalaria glabrata. Embryos of different age groups and adults were studied; alkaline phosphatase activity was seen in very young embryos in the shell field invagination prior to the secretion of any shell material, while peroxidase activity was present from the start of the periostracum production. Acid phosphatase, found in considerable amounts in yolk granules and albumen cells, appeared in the embryonic shell-forming tissue in relatively few Golgi stacks. Tartrate-resistant phosphatase was not present in embryos, but was found in adults in the same zone of the mantle edge as acid phosphatase. Using the enzymes as cell markers, the differentiation of the embryonic shell-forming tissue to the different zones of the adult mantle edge could clearly be followed.  相似文献   

7.
Oral administration of antiulcerogenic drug ranitidine significantly inhibits glucose and amino acid uptake in small intestinal segments. It also inhibits activities of brush border membrane disaccharidases and alkaline phosphatase but increases the activity of leucine aminopeptidase. Kinetic analysis reveals noncompetitive and mixed type of inhibition for disaccharidases and alkaline phosphatase, respectively. In vitro addition of the drug to membrane preparation shows similar type of results as seen in vivo with the inhibition constant (ki) for sucrase, lactase, maltase and alkaline phosphatase as 12.5, 5, 11.5 and 19.5 mM, respectively.  相似文献   

8.
The gene encoding Thermus caldophilus GK24 (Tca) alkaline phosphatase was cloned into Escherichia coli. The primary structure of Tca alkaline phosphatase was deduced from its nucleotide sequence. The Tca alkaline phosphatase precursor, including the signal peptide sequence, was comprised of 501 amino acid residues. Its molecular mass was determined to be 54? omitted?760 Da. On the alignment of the amino acid sequence, Tca alkaline phosphatase showed sequence homology with the microbial alkaline phosphatases, 20% identity with E. coli alkaline phosphatase and 22% Bacillus subtilis (Bsu) alkaline phosphatases. High sequence identity was observed in the regions containing the Ser-102 residue of the active site, the zinc and magnesium binding sites of E. coli alkaline phosphatase. Comparison of Tca alkaline phosphatase and E. coli alkaline phosphatase structures suggests that the reduced activity of the Tca alkaline phosphatase, in the presence of zinc, is directly involved in some of the different metal binding sites. Heat-stable Tca alkaline phosphatase activity was detected in E. coli YK537, harboring pJRAP.  相似文献   

9.
1. The biochemical development and histochemical localisation of phosphomonoesterases in the testes of prepuberal chicks have been studied. 2. Maximum acid phosphatase activity was observed at 12 weeks with a decrease in enzyme activity after this age, whereas alkaline phosphatase activity fluctuated with age. 3. Acid phosphatase activity in chicks was similar to that of the cockerel in being tartarate-insensitive. 4. There was a low level of significant correlation between acid phosphatase activity and testes weight. 5. Both alkaline and acid phosphatase activities were observed in the basement membrane of the seminiferous tubules, and acid phosphatase activity also in the various spermatogenic elements. 6. The results suggest that acid phosphatase is more involved in spermatogenesis, and more widely distributed than alkaline phosphatase in testicular tissue during testicular development.  相似文献   

10.
1. Acid and alkaline phosphatase activities were studied in rat and dog aortic muscle using p-nitrophenyl phosphate (p-NPP) as the substrate. Alkaline phosphatase activity was quite comparable to acid phosphatase activity in rat aortic microsomes as well as further purified plasma membranes, but considerably lower than acid phosphatase activity in dog aortic membranes. 2. Subcellular distribution of acid and alkaline phosphatase activities in these vascular muscles indicated that alkaline phosphatases and a large portion of acid phosphatase activities were primarily associated with plasma membranes and the distribution of acid phosphatase showed little resemblance to that of N-acetyl-beta-glucosaminidase, a lysosomal marker enzyme. 3. The rat aortic plasmalemmal acid and alkaline phosphatase activities responded very differently to magnesium, fluoride, vanadate and EDTA. The alkaline phosphatase was more susceptible to heat inactivation than acid phosphatase. 4. These results suggest that these two phosphatases are likely to be two different enzymes in the smooth muscle plasma membranes. The implication of the present findings is discussed in relation to the alteration of these phosphatases in hypertensive vascular diseases.  相似文献   

11.
The effect of exogenous orthophosphate and mutations in regulatory genes of alkaline phosphatase on the level of nonspecific acid phosphatase was studied. The level of this enzyme as well as the level of alkaline phosphatase were shown to be regulated by exogenous orthophosphate being derepressed under phosphate starvation. The derepression of acid phosphatase is accompanied by more rapid secretion of enzyme from membranes to soluble fraction. Mutations in all the four regulatory genes decrease the level of enzyme in cells. Genes phoR and phoS, participating in regulation of alkaline phosphatase, are required for the derepression of acid phosphatase under the conditions of phosphate starvation.  相似文献   

12.
H W Volk  P Kugler 《Histochemistry》1987,86(5):525-529
We applied cytochemical procedures to demonstrate the presence of acid and alkaline phosphatase in the visceral yolk-sac endoderm of rats using frozen, aldehyde-fixed tissue with cerium as the capture agent. This procedure allowed more detailed topochemical localization than was possible using unfrozen tissue or with lead as the capture agent. Acid phosphatase was found to be present in lysosomes as well as in a small number of apical canaliculi, which are thought to be recycling structures of the cell membranes in endodermal cells. Reaction products of alkaline phosphatase were observed on the outer surface of apical, lateral, and basal cell membranes. In addition, some apical vacuoles contained alkaline phosphatase, and more apical canaliculi were positive for alkaline phosphatase than for acid phosphatase. However, most of the apical canaliculi were negative for both enzymes. It is suggested that acid and alkaline phosphatase are taken up by different numbers of apical canaliculi during the detachment of apical canaliculi from lysosomes and resorption vacuoles.  相似文献   

13.
The histology, fine structure and histochemistry of the digestive gland of Lymnaea stagnalis was examined before and after treatment with a crude water extract of a powerful molluscicidal plant, Detarium microcarpum. The results obtained indicate that the molluscicidal extract induces necrosis in the digestive gland typified optically by cellular oedaema and nuclear pyknosis. At electron microscope level molluscicide treatment is seen to induce a major vacuolation and fragmentation of the cytoplasm. Lysosomal acid phosphatase and lysosomal integrity however is preserved. Histochemically, both acid and alkaline phosphatase appear to survive treatment very well. In treated tissues there is a shift of alkaline phosphatase from the brush border to the lumen. Molluscicide treatment results in a distinct inhibition of ATPase activity which appears to be a characteristic feature of induced cell death.  相似文献   

14.
Acid and alkaline phosphatase activities in culture liquid and mycelial extract during autolysis were studied in seven fungi of the general Ascomycotina, Basidiomycotina and Zygomycotina. High activities of extracellular and mycelial extract acid phosphatase and lower activities of alkaline phosphatase were found in Ascomycotina, and acid phosphatase was present in Basidiomycotina. In Zygomycotina only mycelial extract alkaline phosphatase activity was detected. A correlation between degree of autolysis, pH and acid phosphatase activity was demonstrated.  相似文献   

15.
The Lata fishes (Ophicephalus punctatus) showed increased alkaline and acid phosphatase activities in liver after immersion for 15-30 days in thyroxine-containing medium (0.025 mug/ml). A single injection of thyroxine (1-2 mug/g of body weight) caused increased acid phosphatase activity in liver of Lata fish in comparison to the controls on the 5th day after experiment but the alkaline phosphatase activity remained unchanged. Both alkaline and acid phosphatases showed increased activities in liver of Lata fishes treated with a single injection of 4 mug of thyroxine per g of body weight on the 5th day. Immersion of Lata fishes in thiourea solution (1 mg/ml) for 15 days did not show any alteration in alkaline or acid phosphatase activities but these enzyme activities decreased after 30 days' immersion in thiourea solution in comparison to the controls. A seasonal variation of alkaline and acid phosphatase activities was observed in liver of Lata fishes. More alkaline phosphatase activity was found in liver of summer fishes than in winter fishes. The winter fishes showed more acid phosphatase activity than the summer fishes. Three consecutive injections of thyroxine (0.1 mug/g of body weight) to toads (Bufo melanostictus) caused increased alkaline and acid phosphatase activities in liver on the 5th day of the experiment, in comparison to the controls.  相似文献   

16.
Rhizobium leguminosarum biovar viceae strain TAL 1236 growing on different organic phosphorus compounds as sources of phosphate exhibited phosphatase activities. The strain was able to produce both acid and alkaline phosphatases. However, its ability to produce alkaline phosphatase was much higher. When cellular phosphate fell to 0.115% of cell protein, cellular and extracellular phosphatase activities were promoted. Mg2+, Co2+ and Ca2+ enhanced slightly the activity of alkaline phosphatase more than acid phosphatase. However, Mn2+ and Fe2+ activated acid phosphatase rather than alkaline phosphatase. It may be concluded that Rh. leguminosarum plays an important role in the release of phosphorus from its organic compounds through the action of phosphatases which can be slightly activated by a range of cations.  相似文献   

17.
G R Dickson 《Histochemistry》1978,57(4):343-347
The ultrastructural localization of alkaline phosphatase was studied in the hypertrophic chondrocyte of the frog (Rana temporaria) by incubating sections of glutaraldehyde fixed tissue in a medium containing sodium beta glycerophosphate and calcium chloride. Control specimens were incubated in substrate free medium. Alkaline phosphatase (orthophosphoric monoester phosphohydrolase) is a high molecular weight glycoprotein that hydrolyses phosphorylated metabolites much as acid phosphatase does except that its action is optimal at an alkaline pH. The results of this investigation showed that alkaline phosphatase activity was present within the cytoplasm and around the plasma membrane of frog hypertrophic chondrocytes. Although only a small proportion of frog hypertrophic chondrocytes demonstrated enzyme activity, there was evidence that this was concentrated within Golgi lamellae and vesicles leaving other organelles unreactive. The finding of alkaline phosphatase activity within Golgi lamellae of hypertrophic chondrocytes is regarded as unusual although postitive reactions within chondrocyte lysosomes have previously been reported (Doty and Schofield, 1976).  相似文献   

18.
Acid phosphatase (EC 3.1.3.2 [EC] ) was extracted from mycelia ofAspergillus niger, then separated and purified into four fractions.These acid phosphatases, designated IA, IB, II and III, hadpH optima at 5.0, 4.5–5.0, 4.5 and 2.5, respectively.None required the presence of divalent cations, and all werestrongly inhibited by NaF. They were non-specific acid phosphatasesbut varied in their activities with various substrates. Thealkaline phosphatase (EG 3.1.3.1 [EC] ) of A. niger was also separatedinto two fractions, alkaline phosphatases I and II. Changes in the activity ratios of these acid and alkaline phosphataseswere studied during culture in a peptone medium. The activityof acid phosphatase II was higher than the others when the culturewas young. The activity of acid phosphatase III increased toa maximum in the actively growing phase, then decreased. Thatof acid phosphatase I became highest in the mature culture.In contrast, the activity of alkaline phosphatase I was higherthan the others in young cultures, while alkaline phosphataseII became dominant in the mature culture. Activities of the various acid and alkaline phosphatases indifferent regions of the growing colonies were also studied.The changing patterns of these enzymes in both liquid and surfacecultures were compared. When A. niger was cultured in a medium containing a low concentrationof phosphate, acid phosphatase activity greatly increased afterthe consumption of phosphate, but alkaline phosphatase activitydid not. 1 The present experiments were carried out, for the most partat the Institute of Applied Microbiology of the University ofTokyo. (Received February 10, 1975; )  相似文献   

19.
Localization and activity of five hydrolases (alkaline phosphatase, adenosine triphosphatase, acid phosphatase, nonspecific esterase and leucylamino-peptidase) were evaluated histochemically in the epididymides of mature dogs. In the ductuli efferentes, cilia and apical parts of the epithelial cells displayed high activity of alkaline phosphatase and adenosine triphosphatase. Strong activity of acid phosphatase, nonspecific esterase and leucylamino-peptidase was present in the basal and supranuclear zones of the epithelium of the ductuli efferentes. Stereocilia of all three segments of the ductus epididymidis showed a high activity of alkaline phosphatase. Positive adenosine triphosphatase reaction was confined to the stereocilia of the initial segment. A complex pattern of acid phosphatase activity was observed in the middle segment. The subdivision of the middle segment in four subsegments was therefore suggested. In the epithelium of the initial segment only a few nonspecific esterase-positive cells were seen. The infranuclear and basal areas of the epithelium in the middle segment and the supranuclear zone of the terminal segment displayed distinct nonspecific esterase activity. The possible contribution of the hydrolases to the function of the epididymis is discussed.  相似文献   

20.
Acid and alkaline phosphatase activity were determined in a small pond over a period of 24 months (64 samples). Activity of each phosphatase enzyme was positively correlated with chlorophyll concentration, viable bacterial count, total phosphate concentration, inorganic phosphate concentration, and temperature. Multiple regression analysis was used to formulate equations that described phosphatase activity in terms of these physical, chemical, and biotic factors. Corrected coefficients of determination were calculated, and the highest values were obtained when all parameters were included in the equation (r 2=0.776 and 0.659 for alkaline and acid phosphatase activity, respectively). However, there was little improvement in ther 2 value obtained when only chlorophyll was used in the equation (r 2=0.654 and 0.624, respectively). Samples were then taken over a further 12 months (25 samples), and observed activity was compared with the activity predicted by application of the previously derived equations. For alkaline phosphatase, the best fit between observed and expected activity was seen with the equation containing all parameters, but for acid phosphatase the best fit was seen with the equation containing only chlorophyll and temperature as the determinants. In both cases there was a good fit between observed and expected data using the equation containing chlorophyll as the sole determinant. From this we have concluded that phytoplankton were the chief producers of phosphatase activity in this pond, although the influence of physical and chemical factors on enzyme activity could not be ignored.  相似文献   

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