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)

Poly-A RNA extracted from the rat liver was translated in a cell-free wheat germ system and a rabbit reticulocyte lysate. The subunit of tryptophan pyrrolase precipitated by specific antiserum after synthesis in vitro has the same molecular weight as the corresponding subunit derived from the rat liver. With specific antiserum prepared against tyrosine aminotransferase, however, a radioactive protein from both the in vitro assays was precipitated with an about 5% higher molecular weight than the tyrosine aminotransferase subunit precipitated from rat liver. The immunological evidence and the comparison of the specific peptide patterns prepared by cyanogen bromide treatment showed that the in vitro product corresponds to tyrosine aminotransferase. Various concentrations of potassium or spermidine used in the wheat germ translation system did not alter the size of the enzyme subunit synthesized. The run of the tyrosine aminotransferase purified form the rat liver in the SDS-polyacrylamide gel electrophoresis was not influenced by treatment with Escherichia coli alkaline phosphatase. The possibility is discussed that the larger enzyme synthesized in vitro represents a precursor molecule which is cleaved proteolytically in vivo.
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PMID:Translation of poly-A RNA from rat liver in vitro. Evidence for a high molecular weight subunit of tyrosine aminotransferase. 615 19

A relationship between the second phase of the nucleolar activity and the variations which the yolk globules undergo in their staining affinities and in their chemical constitution has been found in growing oocytes o Murex trunculus. The results obtained enable us to recognize that the different staining affinities among the initial intermediate and definitive yolk granules correlate with the variations in their chemical constitution. The variations are due to the lack of proteins with disulfide groups, tryptophan, indolic and phenolic substances and tyrosine in the initial yolk globules, substances which, on the other hand, are found in both intermediate and final globules. Furthermore, the final globules are lacking in lipids. The presence of both acid and alkaline phosphatase activities is limited mostly to the initial yolk globules. It was possible to deduce from the chemical constitution in the nucleus of the oocytes under examination that the phase in which the nucleous modifies its content of chemical substances and when the transformation in the chemical constitution of the yolk globules occurs, is not coincidental. Both of these phenomena occur when vitellogenesis is advances although the nucleus undergoes vacuolization through out the time in which previtellogenesis passes to vitellogenesis. That the presence of the hydrolytic enzymes is correlated with nucleolar activity and that their probable role is connected with the yolk transformation and subsequent reconstruction is discussed.
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PMID:Structural and cytochemical features of the yolk globules and of the nucleolus in the growing oocytes of the mollusc Murex trunculus L. 617 5

Two enzyme forms of alkaline phosphatase have been partially purified from the medium spent for the culture of HUH-6 clone 5 cells, which were originally derived from hepatoblastoma tissue. The purification methods used are ammonium sulfate precipitation, ethanol precipitation, diethylaminoethyl cellulose chromatography, Affi-Gel Blue chromatography, and Sephadex G-200 gel filtration. These alkaline phosphatases have been characterized by thermostability, inhibition, and immunological and electrophoretic studies. Both are L-phenylalanine and L-tryptophan sensitive and L-homoarginine and L-leucylglycylglycine insensitive, and both react with an antiserum against intestinal alkaline phosphatase. The major enzyme form is a neuraminidase-cleavable, moderately thermostable isoenzyme which on polyacrylamide gel shows an electrophoretic mobility similar to that of liver alkaline phosphatase. The minor enzyme form is a neuraminidase-uncleavable, thermolabile isoenzyme which shows an intermediate electrophoretic mobility between liver and hepatoma alkaline phosphatases. The molecular weights of the major and minor enzymes have been estimated by gel filtration to be 170,000 and 110,000, respectively. These results support the conclusion that the two enzyme forms of HUH-6 alkaline phosphatase are intestinal in type, with the major enzyme form closely resembling hepatoma and oncoamnionic alkaline phosphatases, and the minor enzyme form resembling "intestine-like liver alkaline phosphatase." HUH-6 clone 5 cell line may be a useful in vitro model to study the regulatory mechanism for phenotypic expression of intestinal-type alkaline phosphatase isoenzymes in liver cancer cells.
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PMID:Intestinal-type alkaline phosphatase produced by human hepatoblastoma cell line HUH-6 clone 5. 631 71

A new affinity label for ribulose bisphosphate carboxylase/oxygenase from Rhodospirillum rubrum, 2-(4-bromoacetamido)anilino-2-deoxypentitol 1,5-bisphosphate, has been prepared, Reductive amination of ribulose-P2 with p-phenylenediamine in the presence of sodium cyanoborohydride yielded an epimeric mixture which was resolved by chromatography on quaternary aminoethyl-Sephadex. Subsequent bromoacetylation of the isolated amino bisphosphates gave reagents A and B (ribo and arabino epimers of 2-(4-bromoacetamido) anilino-2-deoxypentitol 1,5-bisphosphate) which were competitive inhibitors of the carboxylase with Ki values of 705 and 104 microM, respectively. Reagent A exhibited no time-dependent effects on the carboxylase in either the deactivated or activated state. Incubation of the enzyme with reagent B in the presence of the essential activators CO2 and Mg2+, however, resulted in an irreversible, time-dependent loss of activity, with a Kinact of 125 microM and a minimal half-time of 7.3 min. Covalent incorporation of [14C]reagent B was directly proportional to the loss of activity, with total inactivation correlating with an incorporation of 1.1 mol of reagent/mol of subunit. Inclusion of the competitive inhibitor 2-carboxyribitol 1,5-bisphosphate protected against inactivation with a concomitant reduction in incorporation. Neither reagent affected the activity of spinach carboxylase. Fractionation of [14C]reagent B-modified enzyme on DEAE-cellulose, subsequent to carboxymethylation and tryptic digestion, revealed two major radioactive peaks of approximately equal area. Digestion of each peak with alkaline phosphatase and rechromatography on DEAE-cellulose resulted in pure peptides I and II. The peptides were identical except in the site of labeling: peptide I contained a modified cysteinyl residue while peptide II contained a modified histidyl residue. Automated Edman degradation established the sequence as (sequence in text) which is located near the NH2 terminus of the enzyme. The lack of reactivity with the spinach enzyme is explained by the deletion of the histidyl residue and the replacement of cysteine by tryptophan in the eukaryotic species. Although the nonconservation of the modified residues argues against a functional role other than maintenance of structural integrity, the extensive homology in this region among seven different species of carboxylase is compatible with the region comprising a portion of the active site.
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PMID:2-(4-Bromoacetamido)anilino-2-deoxypentitol 1,5-bisphosphate, a new affinity label for ribulose bisphosphate carboxylase/oxygenase from Rhodospirillum rubrum. Determination of reaction parameters and characterization of an active site peptide. 642 17

Parallel changes in the enzyme activities of CA2+ATPase and alkaline phosphatase were observed in HeLa cells. Both enzymes were inhibited to a similar degree by L-phenylalanine, L-tryptophan, and L-leucine, while being relatively resistant to L-homoarginine. Exposure to heat (56 degrees C, 60 degrees C, and 65 degrees C) resulted in a loss of both enzyme activities. Both alkaline phosphatase and Ca2+ ATPase, when treated with EGTA, required Ca2+ for the restoration of activity. Cells grown in the presence of agents that affect alkaline phosphatase (dexamethasone, butyric acid, and hyperosmolar NaCl) showed similar changes in the activities of both enzymes.
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PMID:Similarities between alkaline phosphatase and Ca2+ ATPase activities in HeLa cells. 645 Jul 71

Very low amounts of ascorbic acid modify alkaline phosphatase fluorescence, absorption and enzymatic activity. A strong quenching of enzyme, tryptophan and tyrosine emission together with evident alterations of the protein absorption characteristics are observed. The catalytic activity inhibition probably reflects a perturbation of the active site environment due to the interaction of ascorbic acid with enzyme aminoacyl residues.
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PMID:Interaction between alkaline phosphatase and ascorbic acid by fluorescence and absorption studies. 665 47

We studied the uptake of D-glucose and L-tryptophan by the small intestine and estimated the activities of the intestinal brush border enzymes (sucrase, lactase, NA+-K+-ATPase and alkaline phosphatase) and lysosomal enzymes in rats receiving T-2 toxin orally. considerable decrease occurred in glucose and tryptophan uptake and in brush border sucrase, lactase and (Na+-K+)-ATPase. Alkaline phosphatase activity and release of lysosomal enzymes (acid phosphatase and acid ribonuclease) was unchanged.
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PMID:Effects of T-2 toxin on glucose and tryptophan uptake and intestinal mucosal enzymes. 671 77

Escherichia coli K-12, which is rich in alkaline phosphatase, exhibits phosphorescence characteristic of tryptophan at room temperature. E coli mutants which do not have alkaline phosphatase do not show long-lived phosphorescence. The phosphorescence spectrum and lifetime of E. coli K-12 was similar to that of purified alkaline phosphatase from E. coli. These results indicate that the long-lived tryptophan phosphorescence in E. coli is likely to be derived from alkaline phosphatase in situ. The temperature dependence of tryptophan phosphorescence life-time of purified alkaline phosphatase and E. coli K-12 differ; this may imply that alkaline phosphatase in E. coli may be associated with the cell envelope and is therefore protected against structural changes in the protein which result in increased phosphorescence decay rates.
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PMID:Phosphorescence of alkaline phosphatase of E. coli in vitro and in situ. 702 28

A new manganese-containing acid phosphatase has been isolated and crystallized from sweet potato tubers. The pure enzyme contains one atom of manganese per Mr = 110,000 polypeptide and shows phosphatase activity toward various phosphate substrates. The pH optimum of the enzyme was 5.8 and the enzyme activity was inhibited by Cu2+, Zn2+, Hg2+, AsO43-, and MoO42-. This stable metalloenzyme is red-violet in color with an intense absorption band at 515 nm (epsilon - 2460). Our electronic, circular dichroism, and electron spin resonance findings strongly indicate that the Mn-valence state of the native enzyme is trivalent. When the Mn-enzyme is excited by the 5145 A line of Ar+ laser, prominent Raman lines at 1230, 1298, 1508, and 1620 cm-1 were detected. This Raman spectrum can probably be interpreted in terms of internal vibration of a coordinated tyrosine phenolate anion. The tryptophan-modified enzyme showed a positive Raman band at 370 cm-1, which is preferentially assigned to a Mn(III)-S streching mode. The modification of the Mn-enzyme by N-bromosuccinimide led to a large decrease in the fluorescence intensity of 335 nm which was dominated by its tryptophan residues within a considerable hydrophobic environment. The acid phosphatase activity was significantly decreased by the tryptophan modification. With respect to the active site donor sets, the Mn(III)-containing acid phosphatase is distinctly different from the Zn(II)-containing alkaline phosphatase. Of interest is also the appreciable similarity of some enzymatic and spectroscopic properties between the present enzyme and uteroferrin.
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PMID:Purification, enzymatic properties, and active site environment of a novel manganese(III)-containing acid phosphatase. 728 28

D-penicillamine, an antirheumatic drug having chelating ability, was investigated for the effects on vitamin B6 and metals at doses ranging from 25 to 600 mg per kg, p.o., or in case of the highest dosing of D-penicillamine, together with s.c. administration of cupric sulfate or pyridoxine hydrochloride for 28 days in rats. The effects were compared with the actions of L- and DL-penicillamine. D-penicillamine increased urinary vitamin B6 excretion and lowered vitamin B6 levels extensively in serum and slightly in the liver. Those changes were also seen with L- and DL-penicillamine. On the other hand, D-penicillamine had no effects on the activities of serum transaminases and alkaline phosphatase and on the urinary excretion of xanthurenic acid after a tryptophan loading. D-Penicillamine, like L- and DL-penicillamine increased the urinary excretion of Cu and Zn and reduced Cu contents both in serum and liver. When Cu was given s.c. concomitantly with D-penicillamine p.o., an enhancement was seen in the effects of D-penicillamine on the urinary excretion of xanthurenic acid and body weight gain, as well as on the serum level of vitamin B6 and serum transaminase activities. Simultaneous injection of vitamin B6 with D-penicillamine produced a recovery in the lowering vitamin B6 levels induced by D-penicillamine in serum and liver and enhanced the urinary excretion of Cu, but did not influence the serum content of Cu. Thus, although the antivitamin B6 activity of D-penicillamine was demonstrated in rats, the degree was slight and was less than that seen with L- or DL-penicillamine. Moreover, the enhancing effect of Cu on the antivitamin B6 activity of D-penicillamine might be explained by the chelate formation between D-penicillamine-pyridoxal complex and Cu.
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PMID:[Effects of D-penicillamine on vitamin B6 and metal ions in rats (author's transl)]. 738 Mar 58


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