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)

Plasma membranes were isolated from the yeast and mycelial forms of Candida albicans as described previously (Marriott, 1975) and examined for the presence of several enzymes. Measurement of specific activities showed enrichment of Mg2+-dependent and Ma+/K+-stimulated Mg2+-dependent adenosine triphosphatase and mannan synthetase, in the plasma membrane fractions from both morphological forms of the organism. However, acid and alkaline phosphatase, NADH oxidase and 5'-nucleotidase showed no such specific location.
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PMID:Enzymic activity of purified plasma membranes from the yeast and mycelial forms of Candida albicans. 17 Mar 63

In this first paper of a series comparing the membranes of normal lymphocyte populations from male outbred Syrian hamsters with those of neoplastic transformants (GD 248) induced by simian virus 40, a method is described for the isolation of representative plasma membrane (PM) fragments from both cell types. Multiple criteria were used to monitor the purity and yield of PM material after cell disruption by nitrogen cavitation and after membrane fractionation by a combination of differential centrifugation and isopyknic ultracentrifugation in dextran density gradients. Lactoperoxidase-catalyzed radioiodination before cell disruption was used as an extrinsic surface marker; Na+,K+-activated ATPase, as well as alkaline phosphatase, was used as intrinsic functional PM markers. The distribution of nuclei, mitochondria, lysosomes, and endoplasmic reticulum (ER) during fractionation was monitored by the measurement of DNA, succinate dehydrogenase and monoamine oxidase, beta-glucuronidase and glucose-6-phosphatase, and NADH:lipoamide oxidoreductase, respectively. According to the three PM markers employed, a 15- to 20-fold purification (over homogenate) and a PM yield of about 65% were obtained for both cell categories, with negligible contamination by DNA, mitochondria, lysosomes, and er. The procedure also allowed recovery of 60% of the mitochondria free of other cell elements.
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PMID:Membranes of normal hamster lymphocytes and lymphoid cells neoplastically transformed by simian virus 40. I. High-yield purification of plasma membrane fragments. 18 92

One hour after a single i.v. dose of 250 mg/kg folic acid, the straight portion of distal tubules in the outer medulla of rat kidneys showed a distinct reduction in succinate dehydrogenase, NADH2-diaphorase, glutamate dehydrogenase, cytochrome oxydase, Na+/K+-ATPase, and acid phosphatase activity. In contrast, the proximal tubules exhibited only a reduction in glutamate dehydrogenase and alkaline phosphatase activity. At this time the straight portion of the distal tubules, whose enzyme activity had changed, showed partly regressive epithelial changes. 24 hours after folic acid administration an even greater reduction in enzyme activity had occurred in the straight portion of distal tubules; these structures also became dilated. The adjacent collecting tubules and the corresponding proximal tubules were also severely dilated, the proximal tubules showing a loss in enzyme acitivities similar to those observed in the distal tubules. 48 hours after folic acid administration the changes largely resembled those observed after 24 hours, but were more pronounced. At this time a tubular regeneration was observed. 72 hours after folic administration extensive normalization of the histological and histochemical changes had occured. It is postulated that a disturbance of the hairpin counter-current mechanism occurs as a result of a direct, concentration-dependent effect of folic acid on the enzymes of the energy supplying metabolism. A dilation in the region of the loop of Henle and the collecting tubules occurs subsequently.
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PMID:Enzyme histochemistry of rat folic acid nephropathy. 19 86

The arginine-specific reagents 2,3-butanedione and phenylglyoxal inactivate pig kidney alkaline phosphatase. As inactivation proceeds there is a progressive fall in Vmax. of the enzyme, but no demonstrable change in the Km value for substrate. Pi, a competitive inhibitor, and AMP, a substrate of the enzyme, protect alkaline phosphatase against the arginine-specific reagents. These effects are explicable by the assumption that the enzyme contains an essential arginine residue at the active site. Protection is also afforded by the uncompetitive inhibitor NADH through a partially competive action against the reagents. Enzyme that has been exposed to the reagents has a decreased sensitivity to NADH inhibition. It is suggested that an arginine residue is important for NADH binding also, although this residue is distinct from that at the catalytic site. The protection given by NADH against loss of activity is indicative of the close proximity of the active and NADH sites.
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PMID:Evidence for the importance of arginine residues in pig kidney alkaline phosphatase. 22 77

1. The interaction of NAD+, NADH and various nucleotide analogues with pig kidney alkaline phosphatase (orthophosphoric-monoester phosphohydrolase (alkaline optimum) EC 3.1.3.1) has been investigated by kinetic means. Some inhibitors act uncompetitively whereas others markedly increase the slopes of double reciprocal plots suggesting they have some affinity for the free enzyme. 2. The compounds seem to bind to alkaline phosphatase through interactions of their bases with a relatively non-specific region of the enzyme, although it is likely that for those nucleotides having some affinity for the free enzyme there is some attraction between the pyrophosphate backbone and the active site. 3. From studies of the effect of NAD+ and NADH on ATPase activity it was concluded that the substrate inhibition that is characteristic of the ATPase activity of alkaline phosphatase originates from binding of ATP to the site assumed to exist for NAD+ and NADH. The potentiation of NAD+-inhibition of ATPase activity by Mg-2+ is probably a result of the depletion of [ATP-4-] the true substrate. The depletion allows NAD+ to complete more effectively for the active site. 4. Binding of NADH is favoured by protonation of an enzymic group with a pK of approx. 9.0 belonging possibly to a tyrosine residue or a zinc hydrate. 5. A large entropy decrease was found to accompany the binding of NAD+ and NADH to alkaline phosphatase. This may be further evidence of an "induced-fit" mechanism previously suspected because of the synergistic inhibitory effects of adenosine and nicotinamide.
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PMID:Nicotinamide-adenine dinucleotide inhibition of pig kidney alkaline phosphatase. 23 67

The organelle pathology of neutrophils in chronic granulocytic leukaemia (CGL) was investigated by analytical subcellular fractionation. There were minor reductions in activity of some granule enzymes with an abnormal distribution in sucrose density gradients of the specific granules. There was a marked reduction of 5'-nucleotidase activity but this is probably related to the relative reduction of the mononuclear cell contamination of the neutrophils isolated from leukaemic patients compared with controls. Another plasma membrane enzyme, NADH-nitroblue tetrazolium reductase, which has a microbicidal role, had increased activity. Neutrophils from patients with CGL had 13% the alkaline phosphatase activity of controls and were compared with neutrophils from women in the third trimester of pregnancy when the activity was increased to 8 times the control level. The latent activity, per cent inhibition by Levamisole, kinetic constants and subcellular distribution of alkaline phosphatase were similar in the three groups. It is suggested that the properties and intracellular localization of alkaline phosphatase are normal in CGL and that there is a quantitative lack of enzyme.
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PMID:Studies on the subcellular organelles of neutrophils in chronic granulocytic leukaemia with special reference to alkaline phosphatase. 28 20

The activities of alkaline and acid phosphatases, glucose dehydrogenase and NADH oxidase were assayed in cell-free extracts of sporogenic and asporogenic mutants of Clostridium botulinum. During growth of both mutants, the activities of alkaline and acid phosphatases were relatively constant, but during sporulation of the sporogenic mutant, the alkaline phosphatase activity rose to a maximum of 70 mumol/min x mg protein whereas the acid phosphatase decreased rapidly before it increased, indicating a possible role in sporogenesis. Glucose dehydrogenase activity was detected only in cell-free extracts of the sporogenic mutant and reached a maximum of 7 mumol/min x mg protein during the endospore maturation stage. The NADH oxidase activity was detected in both mutants. The NADH oxidase seems to stimulate glucose oxidation in both mutants during growth and the dehydrogenation processes of the butyric type of fermentation during spore formation in the sporogenic mutant. The findings suggest that increased glucose dehydrogenase activity in C. botulinum, as in Bacillus species, may serve as a spore event marker and that alkaline and acid phosphatases may play a regulatory role in anaerobic sporulation metabolism.
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PMID:Activity of some enzymes during growth and sporulation of Clostridium botulinum type E. 39 19

Mycotoxic porcine nephropathy was induced by p.o. administration of crystalline ochratoxin A for periods of 5 days, 3 months and 2 years. Enzyme activities of the renal tissue were studied histochemically. These were NADH-tetrazolium reductase, NADPH-tetrazolium reductase, lactate dehydrogenase, isocitrate dehydrogenase, succinate dehydrogenase, glucose-6-phosphate dehydrogenase, alpha-glycerophosphate dehydrogenase, unspecific acid phosphatase and unspecific alkaline phosphatase. The activity of NADH-tetrazolium reductase and succinate dehydrogenase was reduced in the proximal tubule of all nephrons after 5 days ochratoxin A exposure and remained reduced after 3 months and 2 years exposure. The effect of ochratoxin A on these enzymes would appear to cause the impairment of proximal tubular function and the morphological changes observed in the proximal tubule in ochratoxin A-induced mycotoxic porcine nephropathy. The localization of alterations in enzyme activity corresponds to the localization of ochratoxin A previously demonstrated in the kidney. The activities of NADPH-tetrazolium reductase, lactate dehydrogenase, glucose-6-phosphate dehydrogenase and unspecific alkaline phosphatase were reduced focally corresponding to the areas with focal tubular atrophy and the degree of reduction was roughly parallel to the degree of atrophy.
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PMID:Ochratoxin A-induced mycotoxic porcine nephropathy: alterations in enzyme activity in tubular cells. 47 26

We describe a mechanized method for centrifugal analyzer determination of sorbitol dehydrogenase in serum, based on conversion of D-fructose to sorbitol with simultaneous oxidation of NADH, in triethanolamine buffer at pH 7.4 and 30 degrees C. The standard curve for this assay is linear to 200 U of activity per liter of serum. The mean within-run precision (CV) of the assay is 0.8%. Results correlate well with those by a spectrophotometric method. In sera from 20 apparently healthy adult humans, sorbitol dehydrogenase activity averaged 1.7 (SD +/- 0.8; range, 1-3) U/L. The mean activity (U/L) for a group of 30 rats was 4.4 (SD, +/- 0.2; range, 3-6); for 20 dogs, 5.8 (SD, +/- 0.7; range 3-9); and for 30 mice, 26.8 (SD +/- 2.1; range, 22-34). To determine the utility of measuring this enzyme in the serum of rats for assessment of hepatotoxicity in drug-safety studies, we compared sorbitol dehydrogenase activity with that of alkaline phosphatase, aspartate aminotransferase, and alanine aminotranferase in the sera of rats treated with thioacetamide or in which the common bile duct has been ligated.
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PMID:Kinetic determination of serum sorbitol dehydrogenase activity with a centrifugal analyzer. 50

If there is a histochemical demonstration of acid phosphatase and lactat dehydrogenase with cryostat-microtom-sections of 30 papillomas of the mucous membran of larynx, pharynx and cavum oris you often can find strong activities in tissue with frequent atypical epithelial cells. Intensive appearances after reactions of NADH-tetrazolium-reduktase are correlated with strong hyperplasies and proliferations of the epithelial tissue. Cell groups in the stroma, which are immuncompetantly are showing an moderate activities of acid and alkaline phosphatase, esterase and NADH-tetrazoliumreduktase.
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PMID:[Papillomas of the mucous membranes of the larynx and pharynx. Relations between enzyme histochemistry and histological classification (author's transl)]. 52 88


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