Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.3.1 (alkaline phosphatase)
 47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human erythrocytes from healthy male donors were fractionated with respect to in vivo age by simple centrifugation in order to characterize changes in the functional integrity of the membrane during the life-span of the cell. The three enzymes, Na/K-ATPase, glyceraldehyde-3-phosphate dehydrogenase and NADH-ferricyanide reductase, were found not to change with age, but significant age-dependent decreases were observed in the cases of acetylcholinesterase, phosphoglycerate kinase, purine nucleoside phosphorylase, adenylate kinase, Mg-ATPase and alkaline phosphatase. The possibility that these changes were attributable to mechanisms other than age-related inactivation, such as reticulocyte contamination, differential resealing and crypticity, was investigated. Only the decrease in acetylcholinesterase could be explained wholly in terms of reticulocyte contamination. A decrease in membrane integrity on ageing was observed, which accounted for approximately half the change in alkaline phosphatase and may have contributed to the other enzyme activity changes. This membrane integrity effect masked a real decrease in the highly cryptic NADH-ferricyanide reductase, this decrease being apparent only after total disaggregation of the membrane with nonionic surfactant.
 ...
PMID:Changes in the activities of some membrane-associated enzymes during in vivo ageing of the normal human erythrocyte. 14 40

A method is presented for the separation of 6-thiopurine bases and ribonucleosides, of sulphate anions and of common purine bases and oxidized purines by means of high-pressure liquid cation-exchange chromatography using a 0.18 X 100 cm column, filled with Beckman M71 resin, and eluted with 0.4M ammonium formate, pH 4.6, at a linear flow velocity of 5.2 cm/min at 50 degrees C. The method has been applied to the separation and quantitative determination of 14C-labeled 6-mercaptopurine metabolites in HClO4 extracts of L5178Y murine lymphoma cells. Distribution patterns of 14C radioactivity within the cells after a 24 h incubation period with (8-14C)-labeled 6-mercaptopurine have been established. The indentification of 6-mercaptopurine metabolites, such as 6-thioxanthosine ribonucleotide, 6-thioinosinic acid, 6-thioguanylic acid, 6-methylthioinosinic acid, and 6-thiouric acid, after the digestion of the extracts with alkaline phosphatase has been confirmed using the behaviour of each compound in enzymatic peak-shifting analyses with purine nucleoside phosphorylase and the corresponding elution volumes of 6-thiopurine bases and ribonucleosides as proofs. According to the specific radioactivity of the (8-14C)-labeled 6-mercaptopurine batch, the amounts of the various 6-mercaptopurine metabolites in about 6% of the total HClO4 extract of 1.6 . 10(8) labeled cells have quantitatively been determined as 1--130 pmol. The intracellular concentration of 6-thiopurines was determined at 1.4 . 10(-5)mol/1.
 ...
PMID:The quantitative determination of metabolites of 6-mercaptopurine in biological materials. III. The determination of 14C-labeled 6-thiopurines in L5178Y cell extracts using high-pressure liquid cation-exchange chromatography. 41 11

6-Mercaptopurine (6MP) metabolism was quantitatively determined in L5178Y murine lymphoma. Cells grown in time-course incubates with [35S]-6MP were extracted with cold perchloric acid, and the buffered extracts were subjected to high-performance liquid cation-exchange chromatography prior to and after hydrolysis with alkaline phosphatase. Free sulfate, 6-thiouric acid, 6-thioxanthosine, 6-thioguanosine, 6-thioinosine, free 6MP, and 6-methylthioinosine were separated from each other; identified in the radiochromatograms by elution volume, UV spectroscopic data, and enzymatic peak-shifting analyses with purine nucleoside phosphorylase; and quantitatively determined by means of 35S radioactivity. Gross intracellular 35S concentrations remained constant at 5 x 10(-5) M after 1 hr of incubation. 6MP metabolism in L5178Y cells was distinguished into an early phase (to 1 hr of incubation) in which 6MP was predominantly catabolized to 6-thiouric acid and free sulfate, into an intermediate phase (to 8 hr) in which substantial amounts of free 6MP and of ribonucleotides of 6-thioxanthosine and 6-thioguanosine were present while the concentrations of nonnucleotide oxidation products sharply decreased, and into a late phase (to 24 hr) in which the ribonucleotides of 6MP, of 6-thioguanosine and, in particular, of 6-methylthioinosine were the most abundant metabolites.
 ...
PMID:Quantitation of intracellular metabolites of [35S]-6-mercaptopurine in L5178Y cells grown in time-course incubates. 47 98

The enzymatic pattern of five enzymes involved in the purine salvage pathway, namely purine nucleoside phosphorylase (EC 2.4.2.1), adenosine deaminase (EC 3.5.4.4), 5'-nucleotidase (EC 3.1.3.5), alkaline phosphatase (EC 3.1.3.1), and hypoxanthine-guanine phosphoribosyltransferase (EC 2.4.2.8) has been evaluated both in human intestinal and breast carcinomas and compared to that of normal tissues. A higher level of hypoxanthine-guanine phosphoribosyltransferase was associated with tumor tissues. This metabolic alteration should lead to an elevated synthesis of nucleotides in cancer cells, might confer selective growth advantages to neoplastic tissues, and account, at least in part, for the difficulties encountered in the chemotherapy of human tumors, by using compounds affecting only the purine de novo biosynthesis.
 ...
PMID:Purine salvage enzyme activities in normal and neoplastic human tissues. 212 39

The genetic structure of two Chukot Evens subpopulations (314 individuals) for electrophoretic protein systems and taste sensitivity to PTC was studied. 17 of the 39 loci were polymorphic (43.59%). The following systems were completely monomorphic: diaphorase NAD H (Dia); glucose-6-phosphate dehydrogenase (G-6-PD); glutamatoxalate transaminase (GOT); carbonic anhydrase (Ca-1); catalase (Ct), lactate dehydrogenase (loci LDH-A and LDH-B); leucine aminopeptidase (Lap); malate dehydrogenase (MDH); purine nucleoside phosphorylase (PNP); superoxide phosphorylase (PNP); superoxide dismutase (SOD); phosphoglucomutase-2 (PGM2); cholinesterase (locus E1); red cell esterase (4 loci); albumin (Alb); hemoglobin (Hb A and B); ceruloplasmin (Cp); and blood, gren, using the standard method. The following systems were polymorphic: red cell acid phosphatase (AcP); phosphoglucomutase-1 (PGM1); 6-phosphogluconate dehydrogenase (PGD); glutamatepyruvate transaminase (GPT); glyoxalase-1 (GLO-1); esterase (EsD); adenilatkinase (AK); alkaline phosphatase (Pp); cholinesterase (locus E2); haptoglobin (Hp); transferrin (Tf); group-specific component (Gc) and ABO, MN, Lewis, P blood groups and taste sensitivity to PTC. The following allele frequencies for polymorphic loci have been detected: AKI = 0.994; GLO = 1I = 0.082; GPT1 = 0.653; AcPA = 0.400; AcPB = 0.599; AcPC = 0.001; PGDA = 0.944; PGM1(1) = 0.906; EsD1 = 0.897; E2+ = 0.048; HpI = 0.394; GcI = 0,919; Tfc = 0.987; r(O) = 0.669; p(A) = 0.184; q(B) = 0.146; M = 0.711; Le = 0.411; P1+ = 0.521; t = 0.295. The genetic structure of Chukot Evens population is significantly nearer to that of the other ethnic groups of the North-East, in comparison with the genetic structure of Evenks of the Middle Siberia.
 ...
PMID:[Genetic structure of the populations of native inhabitants in the northeastern USSR. V. The Chukot Evens]. 293 99

The enzymatic inosine 5'-monophosphate assay described by Grassl [in, Methods of Enzymatic Analysis (H. U. Bergman, ed.), pp. 2168-2171, Academic Press, New York (1974)] is highly nonspecific, as ITP, ATP, ADP, AMP, and adenosine react stoichiometrically. The reactivity with the adenine derivatives is due to the tri- and diphosphatase activity of alkaline phosphatase (AP), coupled with adenosine deaminase (and possibly AMP deaminase) contamination of commercially available preparations of AP, purine-nucleoside phosphorylase, and/or xanthine oxidase. The inclusion of coformycin (0.05 microgram/ml), a potent inhibitor of these deaminases, completely eliminated the cross-reactivity. ITP, however, still reacted stoichiometrically due to the tri- and diphosphatase activity of AP. Meyer and Terjung [Amer. J. Physiol. 237 C111-C118 (1979)] introduced a modification of Grassl's procedure, substituting 5'-nucleotidase for AP. It has been found that this disallows reactivity with ATP, ADP, and ITP but that AMP and adenosine still react completely. Coformycin prevents this cross-reactivity. It is therefore recommended that the assay be carried out with 5'-nucleotidase (instead of AP) and coformycin, in order to achieve a more specific assay, and one more suitable for use with whole tissue extracts.
 ...
PMID:An enzymatic inosine 5'-monophosphate assay of increased specificity. 298 81

3-Deazaguanosine containing a 14C label in the ribose moiety was prepared using [U-14C]inosine as the [14C] ribose donor and commercial purine-nucleoside phosphorylase (EC 2.4.2.1) both to degrade the inosine, in the presence of phosphate, and to synthesize [14C-ribosyl]3-deazaguanosine in reduced phosphate and an excess of 3-deazaguanine. Purification was by high-pressure liquid chromatography (HPLC). [14C-ribosyl]3-Deazaguanosine was metabolized by Chinese hamster ovary cells to two metabolites, one major and one minor, eluting in the triphosphate region after HPLC analysis, and appeared to be incorporated into perchloric acid-insoluble material. Cell line TGR-3, deficient in hypoxanthine-guanine phosphoribosyltransferase (EC 2.4.2.8) and resistant to 3-deazaguanine, also formed both metabolites. Line TGR-1/DGRR-9, deficient in hypoxanthine-guanine phosphoribosyltransferase and resistant to both 3-deazaguanine and 3-deazaguanosine, formed greatly reduced levels of the major metabolite. 3-Deazaguanosine 5'-triphosphate, prepared enzymically from authentic 3-deazaguanosine 5'-monophosphate, co-eluted with the major metabolite peak during HPLC analysis. Treatment of a metabolite-containing extract with bacterial alkaline phosphatase (EC 3.1.3.1) resulted in the formation of 3-deazaguanosine. These observations indicate that 3-deazaguanosine can be metabolized, in Chinese hamster ovary cells, to the triphosphate derivative in lieu of the action of hypoxanthine-guanine phosphoribosyltransferase.
 ...
PMID:3-Deazaguanosine is metabolized to the triphosphate derivative in Chinese hamster cells deficient in hypoxanthine-guanine phosphoribosyltransferase. 370 Mar 97

The rat brains homogenized with different media (sucrose, ethylene glycol, dimethyl sulfoxide and urea) yielded different amounts of microsomal fractions. The dielectric constant, density and viscosity of the homogenization media did not correlate with the amount of microsomes separated by differential centrifugation. The homogenization media containing dimethyl sulfoxide were the most efficient for the isolation of rat brain microsomes. The increase in the yield was up to 4-fold when 50% (v/v) dimethyl sulfoxide was employed. Microsomes isolated in this manner were analogous to those obtained from isotonic sucrose solution, as was demonstrated by their chemical and enzymatic (5'-nucleotidase, adenosine deaminase, guanine deaminase, purine-nucleoside phosphorylase, lactate, malate and glutamate dehydrogenases, amine oxidase fumarate hydratase, acid and alkaline phosphatase, acetylcholinesterase, NADPH-cytochrome c reductase, catalase and thiamine-diphosphatase) characterization.
 ...
PMID:An improved method for the preparation of rat brain microsomes. 371 74

Nucleotide pyrophosphatase and phosphodiesterase I activities were determined in sera from 126 patients with different types of liver disease and in two additional groups of patients with intra- and extrahepatic cholestasis, respectively. Both activities probably represent the same enzyme, and were positively correlated with alkaline phosphatase, lipoprotein X, and several other tests reflecting cholestasis. Also, we found by discriminant analysis that tests for cholestasis frequently replaced the results of both enzymes. In some groups of liver disease, nucleotide pyrophosphatase and phosphodiesterase I were correlated with the concentrations of prealbumin and albumin. The sensitivity of phosphodiesterase I (and nucleotide phosphatase) is rather low when compared with alkaline phosphatase, and we do not recommend it for use in the clinical routine. Nevertheless, it appears to be of potential value for studies on classification of liver diseases, adding information to a panel of 20 commonly used "liver tests" by appearing in some of the best four test-sets for distinguishing between groups of liver disease by discriminant analysis.
 ...
PMID:Usefulness of serum nucleotide pyrophosphatase and phosphodiesterase I activities in classifying liver disease. 611 26

The genetic structure of three Asiatic eskimos subpopulations (402 individuals), five coast chuckchies subpopulations (1793 individuals) and three reindeer chuckchies subpopulations (559 individuals) have been studied for 26 electrophoretic protein systems (33 loci). These are: adenilate-kinase (AK), diaphorase NAD X H (Dia), glyoxalase-1 (GLO-1), glucose-6-phosphate dehydrogenase (6GPT), glutamatpyruvate transaminase (GPT), glutamicoxalate transaminase (GOT), carbonic anhydrase-1 (Ca-1), catalase (Ct), acid phosphatase (AcP), lactate dehydrogenase (loci LDH-A and LDH-B), leucine aminopeptidase (Lap), malatedehydrogenase (MDH), purine nucleoside phosphorylase (PNP), superoxide dismutase (Sod), 6-phosphogluconate dehydrogenase (PGD), phosphoglucomutase (loci PGM1 and PGM2), cholinesterase (loci c1--c5), alkaline phosphatase (Pp), esterase D (EsD), red cell esterase (Est) - 4 loci, albumin (Alb), haptoglobin (Hp), hemoglobine (Hb A and B), group-specific component (Gc), transferrin (Tf), ceruloplasmin (Cp). In addition, AB0 and Rh system blood groups and phenyl thiocarbamide taste sensitivity (PTC) have been studied. 12 of 36 loci are polymorphic (33.33%), heterozygosity for all loci in eskimos, coastal and reindeer chuckchies being 0.118 +/- 0.005, 0.130 +/- 0.002 and 0.120 +/- 0.004, respectively. These estimates do not differ essentially from heterozygosity at these loci for mongoloid groups living further south. The test for interpopulation heterogeneity has permitted to estimate contribution of the loci to the differentiation of these populations. The least heterogeneity has been found at loci where gene frequency distribution is the most specific for these ethnic groups.
 ...
PMID:[Genetic structure of the populations of native inhabitants in the northeastern USSR. III. Asiatic Eskimos and the coast and reindeer Chukchi]. 643 3


1 2 Next >>