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)

A novel mobilizable intracellular compartment was identified in human neutrophils by latent alkaline phosphatase activity. This compartment is mobilized to the plasma membrane much more readily than any identified granule subset and has kinetics of up-regulation in the membrane similar to those reported for a variety of receptor proteins. Triton X-100 permeabilization of both intact human neutrophils and subcellular fractions obtained by density-gradient centrifugation revealed that 70 percent of the alkaline phosphatase is located in an intracellular compartment distinct from primary, secondary, and gelatinase granules and from the plasma membrane. This compartment fully translocates to the plasma membrane after stimulation with nanomolar concentrations of the chemotactic peptide N-formylmethionylleucylphenylalanine.
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PMID:Chemoattractant-regulated mobilization of a novel intracellular compartment in human neutrophils. 362 36

A 15-kilodalton protein has been identified as a major component of the residual protein fraction of mouse epididymal/vas spermatozoal heads, demembraned by treatment with Triton X-100 and sequentially extracted with 1 M NaCl/2-mercaptoethanol/DNase I. Two-dimensional electrophoresis of that protein before and after treatment with alkaline phosphatase indicated that it is present in epididymal/vas spermatozoa as a series of five differentially phosphorylated molecules with pI 6.0-7.0. Cyto-immunofluorescence with an affinity-purified antibody to the 15-kDa protein localized that protein to a circumscribed region of the demembraned mouse sperm head mediad from the dorsal margin. By radioimmunoassay, the 15-kDa protein was shown to be sperm-unique and species-specific. The antibody was nonreactive with homogenates of meiotic spermatogenic cells and round spermatids (stages 1-11) but was reactive with a non-phosphorylated 15.5-kDa protein of elongating spermatids (stages 12-16) and testicular spermatozoa. Following alkaline phosphatase treatment, the spermatozoal 15-kDa protein migrated to the position of the spermatidal 15.5-kDa protein on a sodium dodecyl sulfate gel. Thus, we conclude that the 15-kDa protein of mouse spermatozoa is synthesized during the elongation phase of spermiogenesis (stages 12-16) and is phosphorylated in the terminal period of that phase and/or after excursion of spermatozoa from the seminiferous tubules.
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PMID:Proteins of demembraned mouse sperm heads. Characterization of a major sperm-unique component. 388 61

Human placental microvillous alkaline phosphatase (M-PLAP) was extracted from microvilli either by butanol extraction or subtilisin proteolysis. The data indicate that subtilisin cleavage of PLAP removes a membrane-binding domain of approximately 2000 molecular weight, leaving the catalytic site intact and the protein in solution. Sequencing studies on the N-terminal 13 amino acids of both the subtilisin-cleaved and uncleaved forms of M-PLAP indicate that the enzyme is anchored to the plasma membranes by its carboxy-terminus. The N-terminal 13 amino acids of A-PLAP were the same as those of M-PLAP. Trypsin solubilization failed to release M-PLAP from these membranes and it appears to cleave a portion of molecular weight of about 9K from the amino terminus, leaving an enzymatically active portion of PLAP associated with the membrane. On SDS gels, subtilisin-cleaved M-PLAP showed an apparent dimeric molecular size larger than that of the original uncleaved enzyme, presumably due to the generation of a less compact conformational state. On starch gels, cleaved M-PLAP showed a single zone of enzyme activity with a mobility sightly greater than that of A-PLAP, which did not require the presence of Triton X-100 to enter the gel. Variations in the apparent molecular sizes of the different allelic forms of PLAP were also observed.
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PMID:Placental alkaline phosphatase integrates via its carboxy-terminus into the microvillous membrane: its allotypes differ in conformation. 390 24

Several approaches were adopted for the disruption and removal of the tegumental surface from protoscoleces of the horse strain of the hydatid organism, Echinococcus granulosus. The effectiveness of each method and the purity of subsequent microthrix-enriched fractions obtained by differential centrifugation were evaluated by electron microscopy, by the amount of protein released and by the degree of enrichment of surface plasma membrane marker enzymes. Incubation in saponin for 10 min produced the purest microtriche preparation, but in low yield; freeze/thawing, incubation in Triton X-100 for 10 min or in saponin for 20 min produced fractions containing significant amounts of relatively pure microtriches, but mild homogenization was a poor method for surface disruption and subsequent isolation of microtriches. Phosphodiesterase, adenosine triphosphatase (total and ouabain-inhibited), leucine aminopeptidase and glutamyltransferase were active in the protoscoleces but none were enriched in any of the microthrix fractions. In contrast, alkaline phosphatase, acid phosphatase, 5' nucleotidase and maltase were enriched significantly in all of the isolated microtriche preparations, which suggests that these enzymes are predominantly surface membrane bound. The protein profiles of the microthrix-enriched fractions, following SDS-PAGE, were basically similar, although there were some qualitative and quantitative differences in the proteins released by each isolation procedure. Three major PAS-staining components were present in all the preparations and these probably originated from the glycocalyx. One of these PAS-positive components, with an approximate molecular weight of 110 kDa, may be a glycoprotein specific to the horse strain of E. granulosus.
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PMID:Isolation, fractionation and partial characterization of the tegumental surface from protoscoleces of the hydatid organism, Echinococcus granulosus. 398 50

Alkaline phosphatase was solubilized from plasma membrane of rat liver with butanol-ol, bile acids or sodium deoxycholate, and electrophoretically compared with a soluble form in serum which was derived from the liver. The three enzyme preparations from the plasma membrane migrated at the same position on polyacrylamide-gel electrophoresis in the presence of either Triton X-100 or sodium dodecyl sulphate. The mobility of them, however, was distinctly different from that of the serum-soluble form of the liver-derived alkaline phosphatase. On the other hand, phosphatidylinositol-specific phospholipase C isolated from Bacillus cereus was used to release alkaline phosphatase from plasma membrane. The released alkaline phosphatase was demonstrated to have the same mobility as the serum-soluble form on polyacrylamide-gel electrophoresis in the presence or absence of detergents. The phospholipase C also converted the butan-1-ol-extracted membrane form into the serum-soluble form. The results suggest that release of alkaline phosphatase from the liver into serum is not simply caused by a detergent effect of bile salts, but involves an enzymic hydrolysis of phosphatidylinositol, with which alkaline phosphatase may strongly interact in the membrane.
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PMID:Electrophoretic characterization of hepatic alkaline phosphatase released by phosphatidylinositol-specific phospholipase C. A comparison with liver membrane and serum-soluble forms. 399 80

A procedure for the purification of alkaline phosphatase from human polymorphonuclear leukocytes is described, involving enzyme solubilisation with Triton X-100 and chromatography on DEAE-Sepharose CL 6B and Cibacron Red F = B-Sepharose 4B. The final enzyme preparation was 244-fold purified and was shown to be capable of hydrolysis of a wide range of phosphorylated substates.
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PMID:Purification and properties of alkaline phosphatase from human polymorphonuclear leukocytes. 400 37

A method for the isolation of intact phagocytic vesicles from guinea pig peritoneal-exudate granulocytes and human peripheral-blood leukocytes is presented. After leukocytes ingested the particles of a stable emulsion of paraffin oil, the uningested emulsion was washed away and the cells were homogenized. The homogenate was placed in the middle of a three-step discontinuous sucrose gradient and centrifuged for 1 hr at 100,000 g. The phagocytic vesicles, containing the low density paraffin-oil particles, were simultaneously washed and collected by floatation, while the other organelles, chiefly granules, sedimented through the lower wash layer, and the particle-free supernatant remained in the middle of the gradient. Emulsion particles stained with Oil Red O were employed to assay the rate of phagocytosis and to mark the location of the particles in subcellular fractions. The dye was extracted from washed cells or cell fractions with dioxane and colorimetrically quantified. The purity of phagocytic vesicles obtained by this method was assessed by electron microscopy, chemical analysis, and assay of enzyme composition. Granule-associated enzymes, acid phosphatase, alkaline phosphatase, beta-glucuronidase, and peroxidase were present in the phagocytic vesicles and originated from the granules. Cyanide-resistant NADH (reduced form of diphosphopyridine nucleotide) oxidase was also found. Enzymes associated with the vesicles exhibited latency to Triton X-100. Uptake of particles and the transfer of total protein and phospholipid into phagocytic vesicles occurred simultaneously Accumulation of acid and alkaline phosphatase in the vesicles continued until phagocytosis ceased. Peroxidase, NADH oxidase, and beta-glucuronidase activities in the phagocytic vesicles, on the other hand, were maximal by 30 min and increased little thereafter even when phagocytosis was still going on.
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PMID:Isolation and properties of phagocytic vesicles from polymorphonuclear leukocytes. 410 63

1. Submandibular glands from four species of mammal have been shown to contain a hyaluronidase active at acid pH; glands from dog and cat had a much higher content of this enzyme than has been found in other sources. 2. Product formation from hyaluronate after 24hr. incubation was almost the same as with testicular hyaluronidase, indicating that the enzyme is an endo-poly-beta-hexosaminidase. 3. When submandibular-gland homogenates were fractionated by the scheme developed for liver by de Duve, Pressman, Gianetto, Wattiaux & Appelmans (1955), all the enzymes assayed, except cytochrome c oxidase, were found to occur partly in the soluble fraction and partly in the particulate fractions. Among the particular fractions, the highest specific activity was found in the heavy-mitochondrial fraction for cytochrome c oxidase, in the microsomal fraction for alkaline phosphatase and in the light-mitochondrial fraction for acid phosphatase, beta-N-acetylhexosaminidase and acid-active hyaluronidase. 4. Release of the enzyme activity from the sedimentable fractions occurred in 0.1% Triton X-100 or after high-speed homogenization. 5. Stimulation of dogs by pilocarpine was found to decrease the hyaluronidase content of the submandibular gland by 5% and to cause the occurrence of a corresponding amount of acid-active hyaluronidase in the submandibular saliva. 6. The results are discussed in relation to the subcellular localization of hyaluronidase.
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PMID:Canine submandibular-gland hyaluronidase. Identification and subcellular distribution. 430 7

An enzyme (L-glycerol 3-phosphate: CMP phosphatidyltransferase) catalyzing the synthesis of phosphatidyl glycerophosphate from CDP-diglyceride and L-glycerol 3-phosphate has been rendered soluble by treatment of the particulate, membrane-containing fraction of E. coli with Triton X-100 and has been partially purified. The enzyme, devoid of phosphatidyl glycerophosphatase activity, is specific for L-glycerol 3-phosphate and is completely dependent upon added Mg(++) or Mn(++) for activity. It has high affinity for CDP-diglyceride and can be used for the assay of this nucleotide. Other properties of the enzyme are also described.
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PMID:Biosynthesis of phosphatidyl glycerophosphate in Escherichia coli. 486 May 77

1. Homogenates of guinea-pig polymorphonuclear leucocytes were separated by differential centrifugation into six particulate fractions and a soluble fraction. 2. The distributions in these fractions of protein, DNA, succinate dehydrogenase, beta-glucuronidase, peroxidase, alkaline phosphatase, acid phosphatase (against p-nitrophenyl phosphate and beta-glycerophosphate), cathepsin, and catalase were compared. 3. Almost all of the DNA sedimented in the first two pellets, indicating that the nuclei were relatively intact. 4. The four hydrolases and peroxidase showed different distribution patterns, although these activities were previously reported to be localized mainly in the single ;granule' fraction isolated from leucocytes. 5. The particles containing peroxidase, acid phosphatase and alkaline phosphatase all exhibited latency. Maximum activity for each enzyme was obtained at roughly similar concentrations of Triton X-100. 6. The acid phosphatase of these cells was distributed between two populations of particles that differed in both sedimentation characteristics and density. The acid phosphatase(s) of the two populations showed slightly different substrate specificities. This bimodal distribution was not an artifact of the procedure used to elicit the cells. 7. Catalase was recovered almost entirely in the soluble fraction and showed no latency in freshly prepared homogenates. No urate oxidase was detected. 8. We conclude that the ;granule' fraction of the polymorphonuclear leucocyte, as isolated by previous workers, contains at least three, probably more, populations of particles with different enzyme contents, and that these cells probably do not contain peroxisomes.
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PMID:The distributions of some granule-associated enzymes in guinea-pig polymorphonuclear leucocytes. 541 96


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