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The precise nature of the variation in cellular copper load against medium copper concentration is defined using a comprehensive logarithmically incremented series of medium copper concentrations ranging from low levels (4.8 p.p.b.) through normal to toxic levels (40 p.p.m.) in which fibroblasts were grown followed by determination of intracellular content. Menkes' fibroblasts showed an unexpected plateau region of stable intracellular copper content against a change in medium concentration of over 100-fold, albeit only when sufficient copper was present in the medium (0.08–8.0 p.p.m.). Thus, Menkes' cells are clearly capable of balancing uptake/efflux providing copper availability allows. Simultaneous analysis of cellular copper and zinc load at various medium copper concentrations shows an indistinguishable intracellular copper:zinc ratio between the two cell lines. The nature of non-labeled copper uptake by fibroblasts over a 40 min and 7 day period is reported. During the 40 min period copper uptake (20 p.p.m.) was essentially the same in both cell lines. However, copper absorbed was superimposed upon large pre-existing copper pools in the case of Menkes' cells only. Advantages of techniques determining non-labeled copper in copper uptake/efflux experiments are discussed in the light of these results. Fibroblast growth studies showed that, compared with normal cells, Menkes' cells are significantly (P < 0.01) more growth sensitive to extended exposure to low copper concentrations. Thus, Menkes' disease appears to be not only a result of copper maldistribution but also a direct result of an inability of Menkes' cells to function normally in low copper environments. 相似文献
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Ewa Sawosz Monika Łukasiewicz Andrzej Łozicki Malwina Sosnowska Sławomir Jaworski Jan Niemiec 《Archives of animal nutrition》2018,72(5):396-406
We hypothesised that copper nanoparticles (NanoCu), because of their high physicochemical reactivity and bioavailability, could be used in much smaller quantities than bulk Cu, consequently reducing excretion of Cu into the environment. The objective of the study was to evaluate the effects of various levels of NanoCu on the development and growth of broiler chickens, in order to establish an optimum level of NanoCu dietary supplementation. Broiler chickens were randomly divided into five groups of 10 birds each. The control group received 7.5 mg Cu/kg feed (standard level) as CuSO4, while groups fed with complexes of NanoCu and starch received 25%, 50%, 75% and 100% of the standard level of Cu used in the control group. Chicken growth and excretion of Cu, Fe and Zn were measured during the growth period from d 7 to 42. At d 42, the slaughter characteristics, the content of Cu, Fe and Zn in the breast muscle and liver, and the oxidative status were analysed. The results indicate that using NanoCu can reduce the standard level of Cu from CuSO4 supplementation by 75% without jeopardising animal growth, and at the same time significantly decreasing Cu excretion into the environment. 相似文献
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Andrea C. Rinaldi 《Biometals》2000,13(1):9-13
In this brief paper, the author reports on a meeting on copper research (2nd International Meeting on Copper Homeostasis and its Disorders: Molecular and Cellular Aspects) recently held in Ravello, Italy (17–21 September 1999). Aimed at elucidating the diverse roles played by copper ions in biology and medicine, as they are currently intensely investigated worldwide, the meeting has been organized around a number of major topics from prominent areas of copper research. These included the molecular and cellular basis of copper transport, molecular advances in Menkes and Wilson's diseases, the involvement of copper in neurodegenerative diseases, the structure and function of copper metalloproteins. 相似文献
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我国铜矿储藏丰富,铜矿开采带来巨大经济利益的同时,也对生态环境造成极大的破坏,这种恶劣的环境严重阻碍了植物的定居,但是自然界物种繁多,总有一些植物能适应这种环境而生存下来.本文通过对狮子山优势植物吸收和积累铜的分析,发现这些植物均能富集较多的铜,在土壤铜含量很高的情况下,依然生长旺盛,没有出现受害症状,成为尾矿上的优势种,并形成了单优群落或多优小群落.这些植物的存在改变了土壤的理化特性,降低了土壤中的重金属的含量,提高了土壤的全N、全P、全K和有机质含量,一定程度上改善了土壤的不良环境,在尾矿的植被恢复和土壤修复中起着非常重要的作用. 相似文献
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AbstractBacteria from two areas in Wales have been extracted and partially identified. The areas are a copper impregnated bog in the Coed-Y-Brenin Forest with low pH and high carbon and copper content, and the Morfa Harlech salt marshes which have neutral pH and lower copper and carbon. Bacillus spp. was the predominant bacterium in both soils, but there was increased diversity of bacteria in the salt marsh soils. Bacteria from the Cu-rich, Coed-Y-Brenin soils showed higher growth densities in nutrient agar plates containing 10, 30 and 100 μg cm?3 Cu than bacteria from the salt marsh soils, indicating that bacteria from the Coed-Y-Brenin soils could tolerate higher copper concentrations. Pseudomonas spp. from both study areas grew better in media with added Cu at low levels. The possibility is discussed that the bacteria play a part in the bioavailability of Cu particularly in the copper-rich Coed-Y-Brenin area. 相似文献
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Gerrit J. Van den Berg Shiguang Yu Annet Van der Heijden Arnoldina G. Lemmens Anton C. Beynen 《Biological trace element research》1993,38(2):107-115
The hypothesis was tested that dietary fructose vs glucose lowers copper solubility in the digesta in the small intestine
of rats, which in turn causes a decreased copper absorption. Male rats were fed adequate-copper (5 mg Cu/kg) diets containing
either fructose or glucose (709.4 g monosaccharide/kg) for a period of 5 wk. Fructose vs glucose significantly lowered copper
concentrations in plasma and the liver, but did not alter hepatic copper mass. Fructose feeding resulted in a significantly
lesser intestinal solubility of copper as based on either a smaller soluble fraction of copper in the liquid phase of small
intestinal contents or a lower copper concentration in the liquid phase. The latter fructose effect can be explained by the
observed fructose-induced increase in volume of liquid phase of intestinal digesta. After administration of a restricted amount
of diet extrinsically labeled with64Cu, rats fed fructose also had significantly lower soluble64Cu fraction in the digesta of the small intestine. Although this study shows that fructose lowered intestinal copper solubility,
only a slight reduction of apparent copper absorption was observed. It is suggested that the fructose-induced lowering of
copper status in part counteracted the fructose effect on copper absorption at the level of the intestinal lumen. 相似文献
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Andrew R. Battle Leone Spiccia Boujemaa Moubaraki Brian W. Skelton 《Inorganica chimica acta》2006,359(1):289-297
Two new copper(II) complexes of the ligand 1,2,4,5-tetrakis(1,4,7-triazacyclononan-1-ylmethyl)benzene (Ldur) have been synthesized and characterized by single crystal X-ray studies. The first, [Cu4Ldur(μ2-OH)4]Cl2(PF6)2 · 8H2O (1), was isolated from a solution of Ldur and Cu2+ at pH 9. Under acidic conditions (pH 3), a polymeric complex, {[Cu4Ldur(μ2-Cl)6](PF6)2 · 10H2O}n (2), crystallized from solution. In both complexes, each of the four triazacyclononane (tacn) rings of the Ldur ligand facially coordinate to separate metal centres. Pairs of Cu(II) centres are then doubly-bridged by hydroxo groups in 1, leading to tetranuclear complex cation units featuring pairs of isolated copper(II) dimers with Cu2(μ2-OH)2 cores folded at the O?O lines. Two forms of the tetranuclear units, featuring slightly different Cu2(μ2-OH)2 core geometries, are present in equal amounts within the crystal lattice. In complex 2, chloro bridging ligands link pairs of Cu(II) centres from neighbouring tetranuclear units, forming a 1D helical polymeric structure. Variable-temperature magnetic susceptibility measurements suggest that the hydroxo-bridged copper(II) centres within one of the tetranuclear units in 1 are weakly antiferromagnetically coupled (J = −27 cm−1), whilst those in the other interact ferromagnetically (J = +19 cm−1). Similar measurements indicate weak ferromagnetic coupling (J = +16 cm−1) for the chloro-bridged copper(II) centres in 2. 相似文献
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JeanClare Seagrave John L. Hanners Wayne Taylor Harold A. O'Brien 《Biological trace element research》1986,10(3):163-173
Copper uptake and distribution with time among cytoplasmic proteins were followed in cultured cells under several conditions:
(1) CHO cells, which cannot synthesize metallothioneins, were labeled with67Cu in the presence of 100 μM ZnCl2; (2) Cdr30F9 cells, which contain some constitutive metallothionein (MT), were labeled in the absence of additional ZnCl2 and; (3) Cdr30F9 cells were labeled in the presence of ZnCl2, under which conditions they synthesized additional metallothioneins. The exogenous67Cu and ZnCl2, where present, were then removed, and the distributions of67Cu among size fractions of the cellular proteins were observed at intervals for 16 h. In addition, a culture identical to
condition (3) above was also treated with 100 μM ZnCl2 during the redistribution period. The67Cu was initially resolved into three peaks by Sephadex G-75 chromatography: high molecular weight, intermediate molecular
weight, and MT. The67Cu in the MT fraction decreased with at
1/2 of 10–12 h. In contrast to this, generally, in cells with a higher initial67Cu bound to metallothionein, there was a progressive increase in the amount of67Cu eluting with the high- and intermediate-molecular-weight fractions. Since no other source of67Cu was available, these experiments suggest that copper stored in MT can be transferred to other proteins in these cells. 相似文献
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Aims: To evaluate the killing of Pseudomonas aeruginosa PAO1 on copper cast alloys and the influence of genes on survival on copper containing medium and surfaces.
Methods and Results: Different strains of P. aeruginosa were inoculated on copper containing medium or different copper cast alloys and the survival rate determined. The survival rates were compared with rates on copper-free medium and stainless steel as control. In addition, the effect of temperature on survival was examined.
Conclusions: Copper cast alloys had been previously shown to be bactericidal to various bacteria, but the mechanism of copper-mediated killing is still not known. In this report, we demonstrate that P. aeruginosa PAO1 is rapidly killed on different copper cast alloys and that genes involved in conferring copper resistance in copper-containing medium also influenced survival on copper cast alloys. We also show that the rate of killing is influenced by temperature.
Significance and Impact of the Study: To use copper surfaces more widely as bactericidal agents in various settings, it is important to understand how genes influence survival on these surfaces. Here we show that genes shown to be involved in copper resistance in P. aeruginosa PAO1 can have an impact on the length of survival time on copper cast alloys under certain conditions. This is an important first step for evaluation of future use of copper surfaces as bactericidal agents. 相似文献
Methods and Results: Different strains of P. aeruginosa were inoculated on copper containing medium or different copper cast alloys and the survival rate determined. The survival rates were compared with rates on copper-free medium and stainless steel as control. In addition, the effect of temperature on survival was examined.
Conclusions: Copper cast alloys had been previously shown to be bactericidal to various bacteria, but the mechanism of copper-mediated killing is still not known. In this report, we demonstrate that P. aeruginosa PAO1 is rapidly killed on different copper cast alloys and that genes involved in conferring copper resistance in copper-containing medium also influenced survival on copper cast alloys. We also show that the rate of killing is influenced by temperature.
Significance and Impact of the Study: To use copper surfaces more widely as bactericidal agents in various settings, it is important to understand how genes influence survival on these surfaces. Here we show that genes shown to be involved in copper resistance in P. aeruginosa PAO1 can have an impact on the length of survival time on copper cast alloys under certain conditions. This is an important first step for evaluation of future use of copper surfaces as bactericidal agents. 相似文献
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Aims: To develop novel polypropylene composite materials with antimicrobial activity by adding different types of copper nanoparticles. Methods and Results: Copper metal (CuP) and copper oxide nanoparticles (CuOP) were embedded in a polypropylene (PP) matrix. These composites present strong antimicrobial behaviour against E. coli that depends on the contact time between the sample and the bacteria. After just 4 h of contact, these samples are able to kill more than 95% of the bacteria. CuOP fillers are much more effective eliminating bacteria than CuP fillers, showing that the antimicrobial property further depends on the type of copper particle. Cu2+ released from the bulk of the composite is responsible for this behaviour. Moreover, PP/CuOP composites present a higher release rate than PP/CuP composites in a short time, explaining the antimicrobial tendency. Conclusions: Polypropylene composites based on copper nanoparticles can kill E. coli bacteria depending on the release rate of Cu2+ from the bulk of the material. CuOP are more effective as antimicrobial filler than CuP. Significance and Impact of the Study: Our findings open up novel applications of these ion‐copper‐delivery plastic materials based on PP with embedded copper nanoparticles with great potential as antimicrobial agents. 相似文献
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The physiologically important copper complexes of oxidized glutathione have been examined by electron spin resonance (ESR) spectroscopy in aqueous solution at neutral pH. Low temperature measurements show that the Cu(II) binding site in oxidized glutathione has the same ligand arrangement as in the copper complexes of S-methylglutathione, glutamine, glutamate and glycine. The site is composed of the amino nitrogens and the carboxyl oxygens of two -glutamyl residues; there is no interaction with amide nitrogens, the sulphur bond or the glycyl carboxyl groups. At high metal to ligand ratios a binuclear species exists, in which each Cu(II) binds only to one -glutamyl residue. The previously reported forbidden transition detected at g = 4 is due to non-specific aggregation and not to spin coupling of intramolecular sites. Liquid solution ESR spectra show the Cu(II)-glutathione complex has a lower mobility than the corresponding Cu(II)-S'-methylglutathione species. From the degree of spectral anisotropy the complex with glutathione is calculated to exist as a dimer. These results demonstrate that the physiologically relevant complex between copper and oxidized glutathione in solution is completely different from the known solid state structure determined by crystallography. 相似文献
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Aspergillus niger and Penicillium chrysogenum were able to grow on Czapek Dox medium amended with elevated concentrations [up to 500 ppm active ingredient (ai)] of the fungicide copper oxychloride. Solubilization of the fungicide in solid medium was evident by the appearance of a clear (halo) zone underneath and around the growing colonies. The halo formed with A. niger, grown on fungicide-containing nitrate nitrogen medium, was found subsequently to enclose concentric rings of newly crystalline precipitate. These crystals were extracted, examined by scanning electron microscopy and IR, and identified as copper oxalate. The supplemented nitrogen source to the medium greatly affected both fungicide solubilization and fungal tolerance. Ratios of fungicide solubilization rate (R(S)) in relation to the colony growth rate (R(G)) were significantly higher on ammonium than on nitrate nitrogen medium for both fungal strains. Growth ratios (the colony extension rate in the presence of a given concentration of the fungicide in relation to the control colony growth rate) of A. niger were markedly lower on ammonium than on nitrate nitrogen medium. The cellular copper contents, taken up from the fungicide, and the medium titratable acidity were higher in ammonium than in nitrate medium for both fungi. These results suggested fungal possession of variable tolerance mechanisms to this fungicide by complexation and/or precipitation of copper in the medium. Additionally, this work emphasizes the activity of fungi in transformation of insoluble inorganic metal-containing fungicides into insoluble organic metal compounds, which has a potentiality in metal cycling in biogeochemical and environmental context. 相似文献
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Magdalena Araya Manuel Olivares Fernando Pizarro Mauricio González Hernán Speisky Ricardo Uauy 《Biometals》2003,16(1):199-204
Relevant biological effects associated with mild to moderate copper deficiency and copper excess are unknown. It is difficult to identify markers of these early changes because limits of the homeostatic range are still undefined and early changes may represent adaptive responses that do not imply necessarily risk of damage. We report here a series of studies carried out to shed light on the responses within the homeostatic range, by assessing classic parameters of copper status in humans at different copper exposure. In adult healthy volunteers that had an estimated daily intake of 0.9 mg Cu/day (approximately 15 g/kg/d), exposure to additional 50–60 g of copper/kg/day for three months or up to 150 g/kg/d for two months resulted in no significant changes of SOD activity in erythrocytes, of copper concentration (in serum, erythrocytes and mononuclear cells) and of serum ceruloplasmin (ANOVA). Neither were found differences by gender or age. As in previous studies in infants, the non-ceruloplasmin copper fraction was positively correlated to serum copper (r=0.58). Assessing variations on copper absorption, infants supplemented/not supplemented with oral copper (80 ug/kg/14 days), at age 1 and 3 months, showed copper absorption close to 80% at both ages; no effect was observed for age or supplementation, suggesting that either these concentrations do not elicit regulatory mechanisms or that at this age down regulation for copper absorption is not efficient. These studies indicate that in the range of the copper homeostasis area the markers tested are not suitable to detect mild changes (within the homeostatic range) of copper metabolism. 相似文献
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Hair zinc and copper: Relationship to hair type and serum concentrations in children and adolescents
The zinc and copper serum and hair concentrations of 691 3-18-y-old girls and boys previously determined as a part of the
Multicentre Study of Atherosclerosis Precursors in Finnish Children and Adolescents were further analyzed in order to find
a possible association between these two zinc and copper indices. The influence of hair color and the diameter of individual
hair strands on hair concentrations were studied by the analysis of covariance. Hair color and serum zinc concentrations were
found to be associated with hair zinc concentrations in boys. Such an association was not found for zinc and copper concentrations
in girls. Hair vs serum concentrations in different age and hair color groups did not show however, a significant relationship
either in copper or in zinc concentrations. The subjects with very low or high serum zinc or copper concentrations did not
usually have extreme hair concentrations and vice versa. However, there were some subjects with low or high serum concentrations
associated with low or high hair concentrations. 相似文献
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Initial Cu++ sorption by Cyclotella meneghiniana Kütz. (Cu++-sensitive) and Chlamydomonas reinhardtii Dangeard (Cu++-resistant) was rapid in the first 5 min of Cu++ incubation with little sorption after 2 h. On a cell to cell basis, Cyclotella sorbed ca. five times more Cu++ from the medium than Chlamydomonas. In MBL medium with EDTA Cyclotella and Chlamydomonas cells sorbed 21.0 and 4.41 nM Cu++/106 cells respectively in 6 h with 0.3 mg Cu++/l in the medium. Proportionally similar quantities of Cu++ were sorbed when the cells were Cu++ incubated in MBL + citrate or filtered lake water. Cleaned cell walls of Cyclotella sorbed little Cu++ (1.7 nM/106 cells) as compared to living cells (17.5 nM Cu++/106 cells) in 3 h. Therefore, in living Cyclotella most of the Cu++ taken up must be absorbed by the protoplasm or perhaps by the organic layer surrounding the silica wall. Cleaned cell walls of Chlamydomonas sorbed 3.5 nM Cu++/106 cells and living Chlamydomonas cells sorbed 2.6 nM Cu++/106 cells. This indicates that most of the Cu++ sorbed by Chlamydomonas cells remained bound to the cell wall and probably did not readily enter into the protoplasm: When placed in Cu++ free medium after Cu++ incubation, Cyclotella and Chlamydomonas cells released 46 and 59% respectively of the Cu++ sorbed. 相似文献