Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.16.3.1 (ceruloplasmin)
 5,074 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The catalytic activity of phosvitin in Fe(II) oxidation and the addition of iron to transferrin were studied under various conditions. It was concluded that the Fe(II) oxidized by phosvitin would bind to apotransferrin, although an appreciable fraction of Fe(III) remained bound to phosvitin. Fe(III) also migrated from phosvitin to apotransferrin. This reaction was first-order with respect to Fe(III)-phosvitin concentration with a half-time (t1/2) of 10 min, and a first-order rate constant, k=0.069min-1, in 700 muM-phosphate buffer, pH 7.2, at 30 degrees C. The catalysis of the oxidation of Fe(III) by phosvitin was proportional to O2 concentration, and is quite different from the relative O2 independence of Fe(II) oxidation as catalysed by ferroxidase. A scheme for the mobilization and transfer of iron in the chicken, including the role of ferroxidase, phosyitin and transferrin, is presented.
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PMID:Iron oxidation and transferrin formation by phosvitin. 0 72

The optimum pH for ceruloplasmin as polyphenol oxidase (EC 1.10.3.2) activity was determined in human serum (pH 5.4) and the serum of conventional laboratory animals--the rat (pH 5.2), mouse (pH 5.2), hamster (pH 5.3), guinea pig (pH 5.4), multimammate mouse (pH 5.2) and rabbit (pH 5.4). Determined at the optimum pH in 0.1M acetate buffer polyphenol oxidase activity fell in the sequence: rat--man--rabbit--mouse--multimammate mouse--hamster--guinea pig. Ceruloplasmin polyphenol oxidase activity was inhibited by 0.1M phosphate buffer in the mouse, rat and multimammate mouse, but not in the other species. It was inhibited by 0.05M citrate and 0.1M phthalate buffer in all the species tested.
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PMID:Serum polyphenol oxidase activity (ceruloplasmin) in conventional laboratory animals and man. 2 13

A literature review of the effect of oral contraceptive (o.c.) use on various metabolic processes is presented. Several studies show an adverse effect of o.c. use on subclinical diabetes and on patients with manifest insulin-independent diabetes. Some researchers have found a beneficial effect of o.c. use on older diabetics. It has not been determined whether the estrogen or gestagen component of o.c.s is responsible for this decrease in glucose tolerance, nor has the mechanism for this effect been discovered. Changes in various plasma protein concentrations have been observed during o.c. use, which affect the blood coagulation and the blood pressure regulation systems. The estrogen component appears to be responsible for the increase in the serum triglyceride concentration during o.c. use; the mechanism is still unknown. Some studies indicate that o.c. use causes an increase in serum cholesterol levels, which could promote gall stone formation. An increase in Vitamin A concentration has been observed during o.c. use. Riboflavin, folic acid, vitamin B 12, and ascorbic acid levels have been shown to decrease during o.c. use. A decrease in pyridoxin levels during o.c. use indicates an increased metabolism of tryptophan to nicotinic acid robosyl-5-phosphate. This would cause a decrease in serotonin production, which could be a cause of the depression experienced by some o.c. users. An increase in the plasma copper and caeruloplasmin levels during o.c. use is apparently due to the estrogen component. An increase in transferrin and the serum iron levels have been observed during o.c. use. Contradictory findings are reported concerning the plasma concentration of zinc.
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PMID:[Metabolic studies under administration of oral contraceptives. A review]. 34 1

1. Purified caeruloplasmin was shown to inhibit lipid autoxidation induced by ascorbic acid or inorganic iron in the following systems: (a) an emulsion of linolenic acid in water; (b) an untreated ox brain homogenate in phosphate buffer; (c) a similar homogenate whose susceptibility to autoxidation had been abolished by dialysis or by heating and then restored by the above pro-oxidants. 2. The optimum conditions for this antioxidant activity were studied. 3. Caeruloplasmin did not inhibit autoxidation by u.v. irradiation in dialysed or preheated homogenates. 4. The apoprotein (without copper) had no antioxidant activity, whereas CuSO4 alone was much less effective as an antioxidant. 5. Iron-free transferrin also had some antioxidant activity.
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PMID:The inhibition of lipid autoxidation by human caeruloplasmin. 59 72

Blood samples from 509 Macushi and 623 Wapishana Amerindians of of Northern Brazil and Southern Guyana have been analyzed with reference to the occurrence of rare variants and genetic polymorphisms of the following 25 systems: (i) Erythrocyte enzymes: acid phosphatase-1, adenosine deaminase, adenylate kinase-k, carbonic anhydrase-1, carbonic anhydrase-2, esterase A1,2,3, esterase D, galactose-1-phosphate uridyltransferase, isocitrate dehydrogenase, lactate dehydrogenase, malate dehydrogenase, nucleoside phosphorylase, peptidase A, peptidase B, phosphoglucomutase 1, phosphoglucomutase 2, phosphogluconate dehydrogenase, phosphohexoseisomerase, triosephosphate isomerase and (ii) Serum proteins: albumin, ceruloplasmin, haptoglobin, hemoglobin A2 and transferrin. Fifteen different rare variants were detected, involving 11 of these systems. In addition, a previously undescribed variant of ESA 1,2,3 which achieves polymorphic proportions in both these tribes is described. Excluding this variant, the frequency of rare variants is 1.1/1000 in 12510 determinations in the Macushi and 4.7/1000 in 15396 determinations in the Wapishana. The ESA 1,2,3 polymorphism was not observed in 382 Makiritare, 232 Yanomama, 146 Piaroa, 404 Cayapo, 190 Kraho and 112 Moro. Irregularities in the intratribal distribution of this polymorphism in the Macushi and Wapishana render a decision as to the tribe of origin impossible at present. Gene frequencies are also given for previously described polymorphisms of 5 systems: haptoglobin, phosphoglucomutase 1, erythrocyte acid phosphatase, esterase D, and galactose-1-phosphate-uridyl-transferase.
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PMID:Genetic studies of the Macushi and Wapishana Indians. I. Rare genetic variants and a "private polymorphism' of esterase A. 87 Apr 12

A study was made of the interaction of plasma ascorbate and ascorbate free radical (AFR) with exogenously added iron. The quantitative determination of AFR has the advantage that transient increases in ascorbate oxidation can be directly monitored by e.p.r. spectroscopy. An AFR signal was found in the plasma of all donors and was unaffected by superoxide dismutase, catalase and the strong iron chelator deferoxamine. These findings and the rapid decrease in AFR under a nitrogen atmosphere suggest that plasma AFR is probably a result of air auto-oxidation. Iron loading of plasma did not affect the intensity of the AFR signal until the iron concentration approached or exceeded the plasma latent iron-binding capacity. In iron-overloaded plasma, the intensity of the AFR signal increased to about 10 times the normal level before decreasing rapidly to undetectable levels after 15-20 min. Determination of plasma ascorbate showed that the disappearance of AFR was due to a complete loss of the vitamin. When 50 microM-ascorbate was loaded with iron in iso-osmotic phosphate buffer there was an increase in the AFR signal, independent of the iron concentration, which was stable at least for 15 min. Thus the rate of ascorbate loss in the iso-osmotic phosphate buffer was considerably lower than in iron-overloaded plasma. The addition of different iron chelators produced comparable effects on the intensity of the AFR signal in both iron-overloaded plasma and ascorbate solution. These results suggest that the characteristic behaviour of plasma AFR after iron loading is due to its specific iron-binding capacity and to plasma ferroxidase activity. The ferroxidase activity of plasma is important to promote the transfer of Fe2+ into transferrin without a transient ascorbate oxidation. Spin-trapping studies with 5,5-dimethyl-1-pyrroline N-oxide and N-t-butyl-alpha-phenylnitrone revealed that iron-overloaded plasma was unable to produce spin-trap adducts even in the presence of 50-300 microM-hydrogen peroxide or 100 microM-azide. Evidence of OH. radical formation was obtained only after the addition of EDTA. Therefore, iron-overloaded plasma itself does not produce a Fenton reaction and, if ascorbate does indeed have a free-radical-mediated pro-oxidant role, it is not detectable in plasma by spin-trapping experiments.
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PMID:Iron-induced ascorbate oxidation in plasma as monitored by ascorbate free radical formation. No spin-trapping evidence for the hydroxyl radical in iron-overloaded plasma. 131 30

We have developed a modified solvent/detergent (S/D) treatment to inactivate viruses in human plasma using 1% w/w final concentration of tri(n-butyl) phosphate (TNBP) and Triton X-100 and an incubation period of 4 h at 30 degrees C. The procedure inactivates > or = 10(6) chimpanzee-infectious doses (CID50) of HBV, > or = 10(5) CID50 of HCV, and > or = 10(6.2) tissue culture infectious doses (TCID50) of HIV. After virus inactivation, eleven plasma batches were lyophilized and 12 batches were deep-frozen until further use. The batches were characterized by extensive laboratory tests including measurement of clotting factors I-XIII, von Willebrand factor, plasminogen, inhibitors of blood coagulation and fibrinolysis, and other clinically important plasma proteins. All parameters were determined before and after S/D treatment. Twelve conventional single donor plasma units served as control. There were no marked losses of activities of clotting factors, antithrombin III, protein C, plasminogen, and C1-esterase inhibitor due to treatment. After the S/D step, the levels of these parameters were within the normal range in all batches. The same holds true for total protein, immunoglobulins, albumin, complement factors C3 and C4, haptoglobin, hemopexin, caeruloplasmin, alpha 1-antitrypsin, and pH. Protein S and alpha 2-antiplasmin activities decreased by about 50% and were frequently found to be slightly below the lower limit of the respective normal range after treatment. The interindividual variations of all proteins analysed were significantly lower than in the single donor plasma units. The S/D procedure did not lead to increases of markers indicating activation of hemostasis.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Manufacture and in vitro characterization of a solvent/detergent-treated human plasma. 144 62

Fe2+, when combined with ceruloplasmin or phosphate, was bactericidal to Escherichia coli at pH 5.0, and when Fe2+, ceruloplasmin, and phosphate were combined, a bactericidal effect was observed under conditions, i.e., short incubation period, in which Fe2+ plus ceruloplasmin and Fe2+ plus phosphate were ineffective. Bactericidal activity increased with the ceruloplasmin or phosphate concentration to a maximum and then decreased as their concentration was further increased. Fe2+ was oxidized in the presence of ceruloplasmin, phosphate, or, in particular, a combination of the two. A bactericidal effect was observed when there was only a partial loss of Fe2+, with more extensive oxidation resulting in a loss of bactericidal activity. The bactericidal effect of Fe2+ plus ceruloplasmin and/or phosphate was unaffected by catalase or superoxide dismutase and was not associated with iodination. Fe-EDTA was also bactericidal at an Fe2+: EDTA molar ratio of 1:0.5, where Fe2+ was partially oxidized. However, in contrast to Fe2+ plus ceruloplasmin and/or phosphate, bactericidal activity was inhibited by catalase and was associated with iodination. Combinations of Fe2+ and Fe3+ were not bactericidal under the conditions employed. A requirement for Fe2+ plus either a product of Fe2+ oxidation or an iron ceruloplasmin and/or phosphate chelate for bactericidal activity is proposed.
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PMID:Bactericidal effect of Fe2+, ceruloplasmin, and phosphate. 158 59

When a ferric citrate complex is prepared from citric acid and ferric chloride, and the pH value left unchanged, a reduction of the iron moiety takes place. Within several hours a substantial yield of ferrous ions can be detected in the solution. When placed in a phosphate buffer pH 7.0 with a suitable detector molecule, oxidative damage to the detector molecule can be observed. Thus, deoxyribose is degraded with the release of thiobarbituric acid-reactive material and benzoate is hydroxylated to form fluorescent dihydroxy products. Damage can be prevented by scavengers of the hydroxyl radical such as mannitol, formate the thiourea, by catalase and by the protein caeruloplasmin, suggesting that Fenton chemistry occurs leading to the formation of hydroxyl radicals.
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PMID:Hydroxyl radical formation from the auto-reduction of a ferric citrate complex. 166 38

An immunoenzymatic method for ceruloplasmin analysis (IEA) based on the use of horseradish peroxidase-labelled monospecific antibodies as markers has been developed. IEA can be used for direct measurements of ceruloplasmin in blood serum, as can be evidenced from the coincidence of calibration plots obtained after the use of potassium-phosphate buffer and ceruloplasmin-free sera. The procedure allows the determination of the total content of ceruloplasmin present in the blood sera of patients with hepatocerebral dystrophies both in the active and inactive forms. The minimum ceruloplasmin concentration detectable by this method is 5 x 10(-9) g/ml. The method was used to determine ceruloplasmin levels in the blood of patients with various grades of hepatocerebral dystrophy. Analysis of blood sera from 6 patients revealed that the ceruloplasmin concentrations determined by IEA were very close, whereas the oxidase activities of this protein differed more than 7-fold. The amount of enzymatically active ceruloplasmin as determined from the oxidase activity made up to 10-68% of the total ceruloplasmin content in the sera, depending of the severity of the pathology.
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PMID:[Immunoenzyme determination of the total level of ceruloplasmin in the serum from patients with hepatocerebral dystrophy]. 174 26


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