Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: 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 study has been made of the progress of involution of the mouse and rat mammary gland using histologic, electron microscopic, histochemical and autoradiographic methods. Particular emphasis has been placed on the morphology, metabolic alterations and activities of histochemically identifiable enzymes, and on the pharmacologic effects of lactation inhibiting agents and cytostatic drugs on lactation and involution. In order to allow a systematic investigation, involution was initiated in rats and mice by ligation of individual gland ducts at various time intervals. Both lactating glands and glands in different phases of involution were thus available in a given animal. The most important observation was that involution, which altogether takes approximately 2 weeks to be complete, involves a three-phase process, each phase being clearly distinguishable by morphologic and histochemical criteria. The first phase comprises approximately 4 days during which production of milk may be reinitiated. The second phase starts on day 5 of involution and constitutes the period of involution per se characterized by appreciable parenchymal cell degradation. The third phase, which starts around day 10, is the period of reorganization to the resting mammary gland. Early in the first phase of involution, substantial alveolar enlargement due to engorgement with milk, together with epithelial flattening, are prominent features. By day 3, the glandular contents decrease again in volume, the number of glandular cells and the constituent cytoplasmic organelles remaining unchanged during this period, except for the diminished appearance of fat droplets. In addition to normal appearing vacuoles with only occasional or sparse protein granules, giant vacuoles containing, in part, several hundred casein granules are found. Their formation appears to be due to increased stacking of granules in distended vacuoles prior to dissociation from the Golgi apparatus. In addition, however, the enhanced reactions of alP (alkaline phosphatase) and ATPase, which are found in the apical plasmalemma, are suggestive of resorptive activities. Protein particles absorbed from the glandular lumen equally appear to have a capacity for fusing into large vacuoles. The large protein granule-containing vacuoles regularly exhibit intense beta-Glu activity. This enzyme would appear to contribute actively to the degradation of excess milk during the first phase of involution. Autoradiographic studies reveal that the synthesis and release of proteins into the secretion is maintained for 3 days. While 3H-tyrosine uptake by the alveolar cells continues unchanged, the incorporation of 3H-palmitic acid into glandular lipoids, and of 3H-fucose into glandular polysaccharides is virtually blocked completely. An immediate reaction of the lipoid metabolism is also indicated by the decrease in 3HBDH activity on the first day of involution...
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PMID:[Involution of the mammary gland. Enzyme histochemistry, elektron microscopy and radioautography (author's transl)]. 18 47

Lipopeptides are potential vaccine candidates with a built-in adjuvant property. To circumvent the present chemical route of synthesis for lipopeptide-antigen conjugates, the lipoprotein property of the pColE2-P9-encoded lysis protein, CelB, was used to create the bacterial fusion plasmid, pKLY3, to produce lipopeptide-antigen chimeras in Escherichia coli. Plasmid pKLY3 is a derivative of pKK233-2 with the origin of replication of the single-stranded DNA phage, fl. Under control of the promoter, ptrc, is the 5' end of the celB gene coding for a lipoprotein signal peptide and the first five amino acids (aa) (CQANY) of the mature lysis protein. As model systems for the synthesis of small and large lipopeptide-antigens, DNA sequences coding for the P2 peptide and E. coli alkaline phosphatase (PhoA) were fused in frame to the region of celB coding for a lipoprotein signal peptide and CQANY. P2 is a 12-aa peptide including a tyrosine phosphorylation site of the epidermal growth factor receptor (EGF-R). Inducible expression of stable lipohexapeptide CQANYV, lipo-CQANY-P2, and lipo-CQANYA-PhoA, was demonstrated. Similar expression was obtained for lipo-CIEGR-P2 and lipo-CIEGRA-PhoA in which IEGR is a cleavage recognition site for the blood coagulation factor, Xa. Like QANY, IEGR is predicted to form a beta-turn structure. The presence of a lipid moiety on the products was confirmed by demonstrating the incorporation of radioactive palmitic acid and inhibition of processing by globomycin. The lipid-modified peptides were also identified by incorporation of radioactive tyrosine, and the nature of the P2 peptide was verified immunologically.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:A fusion plasmid for the synthesis of lipopeptide-antigen chimeras in Escherichia coli. 162 39

The palmitic acid binding capacity of cytosolic proteins in three preparations obtained by differential scraping of bovine intestinal mucosa were compared. The data indicated that the palmitic acid binding activities depended on the position that the cells occupied along the crypt-villus axis, as shown from the level of alkaline phosphatase activity. Proteins with palmitate binding properties in the high- and low-molecular-weight cytosolic proteins in the villus zone bound 1.24 +/- 0.41 and 1.54 +/- 0.16 pmol palminate/micrograms protein respectively. The binding decreased to 0.50 +/- 0.25 and 1.10 +/- 0.23 pmol palmitate/micrograms for the proteins in the crypt zone. Ammonium sulphate fractionation and gel filtration chromatography indicated that the low-molecular-weight cytosolic proteins obtained from light mucosal scrapings contained the highest palmitate binding activity. These results suggest that the cytosolic proteins located in the villus zone may play a role in the absorption of fatty acids.
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PMID:The palmitic acid binding properties of cytosolic proteins located in the villus and crypt zones of bovine intestinal mucosa. 180 23

Pulmonary surfactant was isolated from human lung homogenate after differential and sucrose density gradient centrifugation. Purification of the isolated material was ascertained by electron microscopy and alkaline phosphatase (AKP) specific activity. Elevated levels of phospholipid/protein ration and AKP specific activity were observed in the purified material when monitored at different stages of purification. Biochemical analysis of the isolated material showed that it consisted of 74.08% lipid, 19.06% protein and relatively smaller amounts of nucleic acids, sialic acid and hexoses. Phosphatidyl choline was the predominant phospholipid whereas triglycerides and cholesterol levels were high among neutral lipids. Gas liquid chromatography of the material showed palmitic acid (16:0) as the major saturated fatty acid. These findings indicated that a large scale isolation of surfactant might be possible and utilized for therapeutic treatment of neonatal respiratory distress syndrome.
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PMID:Sequential isolation and biochemical analysis of pulmonary surfactant from human lung homogenate. 235 Mar 58

The amount and composition of lysophosphatidate present in different rat tissues have been estimated by an internal standard method in which a synthetic unnatural isomer (1-heptadecanoyl-rac-glycerol-3-phosphate) was added to the total lipid extracts, and the fatty acid composition of purified lysophosphatidate was determined. Lipids from tissues were extracted under acidic conditions, and the lysophosphatidate was purified by solvent partitions followed by thin-layer chromatography in multiple solvent systems. The purified lipid was shown to be 1-acyl-sn-glycerol-3-phosphate by chromatographic and chemical analysis, by its resistance to hydrolysis when treated with phospholipase A2 and also by its complete conversion to 1-acyl-sn-glycerol when treated with alkaline phosphatase. The fatty acid constituents of this lipid were determined by gas-liquid chromatography of the derived methyl esters. The concentrations (nmol/g of tissue) of lysophosphatidate in various tissues were: 86.2 +/- 4.2 in brain, 60.3 +/- 6.3 in liver, 46.4 +/- 6.5 in kidney, 30.6 +/- 5.0 in testis, 22.3 in heart and 19.3 in lung. Mostly (80%) saturated fatty acids were found to be present in this lyso lipid. A significantly high level of stearic acid was present in this lipid from all the tissues (50-60% in liver, kidney, brain and testis, and about 40% in heart and lung) compared to palmitic acid (10-15% in liver, kidney and brain and 25-30% in testis, heart and lung). The fatty acid compositions of phosphatidic acid, the putative product of lysophosphatidate acylation, from different tissues were also determined and palmitate was found to be the major saturated fatty acid.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Quantification, characterization and fatty acid composition of lysophosphatidic acid in different rat tissues. 275 10

Membranous and soluble forms of rat liver alkaline phosphatase were selectively prepared by extracting microsomes with n-butanol at pH 8.5 and 5.5, respectively, and purified in homogeneous forms by the method previously established (Miki et al. (1986) Eur. J. Biochem. 160, 41-48). When subjected to polyacrylamide gel electrophoresis, the two forms migrated to the same position in the presence of sodium dodecyl sulfate, while the membranous form remained at the top of gels in the absence of the detergent. Treatment of the membranous form with phosphatidylinositol-specific phospholipase C resulted in its conversion to a soluble form with the same electrophoretic mobility even in the absence of the detergent as that of the soluble form extracted at pH 5.5. Automated Edman degradation analysis showed that the two forms have the same N-terminal amino acid sequence up to the 30th residue determined. Chemical analyses of hydrolysates of the two forms by gas-liquid chromatography demonstrated that the membranous form contains palmitic acid, stearic acid, and inositol, while the soluble form contains inositol but is devoid of the fatty acids. Taken together, these results suggest that rat liver alkaline phosphatase is covalently attached to phosphatidylinositol acylated with palmitic acid and stearic acid, which functions as the membrane-anchoring domain of the enzyme molecule.
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PMID:Chemical identification of lipid components in the membranous form of rat liver alkaline phosphatase. 283 51

Phosphatidylinositol anchors human placental-type alkaline phosphatase (PLAP) to both syncytiotrophoblast and tumour cell plasma membranes. PLAP activity was released from isolated human placental syncytiotrophoblast plasma membranes and the surface of tumour cells with a phospholipase C from Bacillus cereus. This was a specific event, not the result of proteolysis or membrane perturbation, but the action of a phosphatidylinositol-specific phospholipase C in the preparation. Soluble PLAP, released with B. cereus phospholipase C and purified by immunoaffinity chromatography, ran on SDS-PAGE as a 66-kDa band. This corresponded to intact PLAP molecules. The protease bromelain cleaved lower-molecular-mass PLAP (64 kDa) from the membranes. Flow cytometry demonstrated that B. cereus phospholipase C released human tumour cell membrane PLAP in preference to other cell-surface molecules. This was in contrast to the non-specific proteolytic action of bromelain or Clostridium perfringens phospholipase C, which had no effect on membrane PLAP expression. Radiolabelling of tumour cells with fatty acids indicated PLAP to be labelled with both [3H]myristic and [3H]palmitic acid. This fatty-acid--PLAP bond was sensitive to pH 10 hydroxylamine treatment indicating an O-ester linkage.
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PMID:Attachment of human placental-type alkaline phosphatase via phosphatidylinositol to syncytiotrophoblast and tumour cell plasma membranes. 312 11

Surface-active material (SF) was isolated from human lung lavage fluid collected at autopsy employing differential and sucrose density gradient centrifugation. The isolated material showed well-defined electron microscopic structure, consisting of clearly preserved, closely packed vesicles with limiting membranes and inclusion bodies. It showed a very high degree of alkaline phosphatase specific activity and was devoid of other subcellular contaminants. The isolated material also showed a high phospholipid/protein ratio and increasing surface activity when monitored at different stages of purification. It contained 68.5% phosphatidylcholine, 11.5% phosphatidylglycerol and relatively smaller amounts of phosphatidylethanolamine and other individual phospholipid (PL) classes. In addition, cholesterol, unesterified fatty acids, triacylglycerols and other neutral lipids were found. Saturated fatty acids, particularly palmitic acid (16:0), predominated in the major PL fractions. However, various fatty acids of which oleic acid (18:1) constituted a large proportion also are present. Chemical analysis of the material showed that besides lipids and proteins, nucleic acids, sialic acid, hexose, amino sugars, nitrogen and phosphorus were present. The delipidated material showed the presence of three to four proteins as characterized by sodium dodecylsulfate (SDS)-polyacrylamide gel electrophoresis, and gel permeation chromatography on Sephadex G-200 resolved two well-separated peaks. The first fraction contained serum-associated 68 kDa protein, while the second fraction had two apoproteins with molecular weights of 34 kDa and 10 kDa. These two proteins were associated with the SF and they, as well as the whole surface-active material, strongly reacted with the antibody directed against the whole SF in a double-diffusion immunoprecipitation assay.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Isolation and chemical composition of surface-active material from human lung lavage. 317 85

Cultured heart muscle cells, but not HeLa cells, oxidize long-chain fatty acids in medium containing dialyzed serum. Addition of chicken serum dialysate (or non-dialized serum) stimulated palmitic acid oxidation by HeLa cells 10 to 20 fold. This serum activity was not eliminated by lipid extraction, ethanol or acid precipitation, alkaline phosphatase treatment, or autoclaving. About 80% was lost after any one of the following treatments: 6N HCl at 110 degrees C for 16 hr, pepsin, Dowex cation exchange at pH 3, or 1N KOH at 100 degrees C for 1 hr. Serum activity was separated into five or more peaks by gel filtration with Sephadex G-10. Each of these peak fractions was further purified by HPLC using a cyanopropyl-bonded resin. Carnitine, which is important for the transport of long-chain fatty acids into mitochondria for oxidation, also stimulated the oxidation of palmitate. However, these serum factors are not known precursors to carnitine since its immediate precursor 4-n-trimethylaminobutyrate, did not stimulate palmitate oxidation. Total carnitine, including that in acylcarnitine compounds, was approximately 15 microM in the chicken sera to give approximately 0.7 microM in the medium. Based on the fraction of total activity accountable by carnitine and fractional stability to acid, alkali, and pepsin, about 75% of the activity is from non-carnitine compounds. Only one of the factors appears to be carnitine or an acylcarnitine derivative. Several lines of evidence suggest that the other factors are peptide compounds.
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PMID:Serum factors that stimulate fatty acid oxidation: properties of factors. 394 93

To identify elements participating in the process of transformation, a bank of genetically altered mutants of Streptococcus pneumoniae with defects in exported proteins was assessed for a decrease in transformation efficiency. One mutant consistently transformed 10-fold less than the parent strain. Sequence analysis and reconstitution of the altered locus revealed a gene, plpA (permease-like protein), which encodes a putative substrate-binding protein belonging to the family of bacterial permeases responsible for peptide transport. The derived amino acid sequence for this gene was 80% similar to AmiA, a peptide-binding protein homologue from pneumococcus, and 50% similar over 230 amino acids to Spo0KA which is a regulatory element in the process of transformation and sporulation in Bacillus subtilis. PlpA fusions to alkaline phosphatase (PhoA) were shown to be membrane associated and labelled with [3H]-palmitic acid, which probably serves as a membrane anchor. Experiments designed to define the roles of the plpA and ami determinants in the process of transformation showed that: (i) mutants with defects in plpA were > 90% transformation deficient while ami mutants exhibited up to a fourfold increase in transformation efficiency; (ii) compared to the parental strain, the onset of competence in an ami mutant occurred earlier in logarithmic growth, whereas the onset was delayed in a plpA mutant; and (iii) the plpA mutation decreases the expression of a competence-regulated locus. Since the permease mutants would fail to bind specific ligands, it seems likely that the substrate-permease interaction modulates the process of transformation.
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PMID:Peptide permeases modulate transformation in Streptococcus pneumoniae. 752 29


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