Copper–zinc superoxide dismutase (Sod1) is a critical antioxidant enzyme that rids the cell of reactive oxygen through the redox cycling of a catalytic copper ion provided by its copper chaperone ...(Ccs). Ccs must first acquire this copper ion, directly or indirectly, from the influx copper transporter, Ctr1. The three proteins of this transport pathway ensure careful trafficking of copper ions from cell entry to target delivery, but the intricacies remain undefined. Biochemical examination of each step in the pathway determined that the activation of the target (Sod1) regulates the Ccs·Ctr1 interaction. Ccs stably interacts with the cytosolic C-terminal tail of Ctr1 (Ctr1c) in a copper-dependent manner. This interaction becomes tripartite upon the addition of an engineered immature form of Sod1 creating a stable Cu(I)-Ctr1c·Ccs·Sod1 heterotrimer in solution. This heterotrimer can also be made by the addition of a preformed Sod1·Ccs heterodimer to Cu(I)-Ctr1c, suggestive of multiple routes to the same destination. Only complete Sod1 activation (i.e. active site copper delivery and intra-subunit disulfide bond formation) breaks the Sod1·Ccs·Ctr1c complex. The results provide a new and extended view of the Sod1 activation pathway(s) originating at cellular copper import.
Mycosynthesis of nanoparticle (NP) production is a potential ecofriendly technology for large scale production. In the present study, copper oxide nanoparticles (CuONPs) have been synthesized from ...the live cell filtrate of the fungus
Penicillium chrysogenum
. The created CuONPs were characterized via several techniques, namely Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM), and energy-dispersive X-ray spectroscopy (EDX). Furthermore, the biosynthesized CuONPs were performed against biofilm forming
Klebsiella oxytoca
ATCC 51,983,
Escherichia coli
ATCC 35,218,
Staphylococcus aureus
ATCC 25,923, and
Bacillus cereus
ATCC 11,778. The anti-bacterial activity result was shown with the zone of inhibition determined to be 14 ± 0.31 mm, 16 ± 0.53 mm, 11 ± 0.57 mm, and 10 ± 0.57 mm respectively.
Klebsiella oxytoca
and
Escherichia coli
were more susceptible to CuONPs with minimal inhibitory concentration (MIC) values 6.25 and 3.12 µg/mL, respectively, while for
Staphylococcus aureus
and
Bacillus cereus
, MIC value was 12.5 and 25 μg/mL, respectively. The minimum biofilm inhibition concentration (MBIC) result was more evident, that the CuONPs have excellent anti-biofilm activity at sub-MIC levels reducing biofilm formation by 49% and 59% against
Klebsiella oxytoca
and
Escherichia coli
, while the results indicated that the MBIC of CuONPs on
Bacillus cereus
and
Staphylococcus aureus
was higher than 200 μg/mL and 256 μg/mL, respectively, suggesting that these CuONPs could not inhibit mature formatted biofilm of
Bacillus cereus
and
Staphylococcus aureus
in vitro. Overall, all the results were clearly confirmed that the CuONPs have excellent anti-biofilm ability against
Klebsiella oxytoca
and
Escherichia coli
. The prepared CuONPs offer a smart approach for biomedical therapy of resistant microorganisms because of its promoted antimicrobial action, but only for specified purposes.
Cisplatin, or cis-diamminedichloridoplatinum(II) cis-PtCl2(NH3)2, is a platinum-based anticancer drug largely used for the treatment of various types of cancers, including testicular, ovarian and ...colorectal carcinomas, sarcomas, and lymphomas. Together with other platinum-based drugs, cisplatin triggers malignant cell death by binding to nuclear DNA, which appears to be the ultimate target. In addition to passive diffusion across the cell membrane, other transport systems, including endocytosis and some active or facilitated transport mechanisms, are currently proposed to play a pivotal role in the uptake of platinum-based drugs. In this review, an updated view of the current literature regarding the intracellular transport and processing of cisplatin will be presented, with special emphasis on the plasma membrane copper permease CTR1, the Cu-transporting ATPases, ATP7A and ATP7B, located in the trans-Golgi network, and the soluble copper chaperone ATOX1. Their role in eliciting cisplatin efficacy and their exploitation as pharmacological targets will be addressed.
This book provides fully updated coverage of the copper production process encompassing topics as diverse as environmental technology for wind and solar energy transmission, treatment of waste ...byproducts, and recycling of electronic scrap for potential alternative technology implementation. The authors examine industrially-grounded treatments of process fundamentals and the beneficiation of raw materials, smelting and converting, hydrometallurgical processes, and refining technology for a mine-to-market perspective, from primary and secondary raw materials extraction to shipping of rod or billet to customers. The modern coverage of the work includes bath smelting processes such as Ausmelt and Isasmelt which have become state-of-the-art in sulfide concentrate smelting and converting.
Copper Active Sites in Biology Solomon, Edward I; Heppner, David E; Johnston, Esther M ...
Chemical reviews,
04/2014, Letnik:
114, Številka:
7
Journal Article
Recenzirano
Odprti dostop
Solomon et al present information on the electronic structure and spectroscopy of copper active sites in biology, including mononuclear Cu(II) sites, binuclear copper sites and electronic structure ...calculations. In addition, they address quercetinase and cofactor biogenesis in the copper amine oxidases.
Abstract
The release of nanoparticles (NPs) to the environment poses an increasing potential threat to biological systems. This study investigated the phytotoxicity and accumulation of copper oxide ...(CuO) NPs to Elsholtzia splendens (a Cu-tolerant plant) under hydroponic conditions. The 50% effective concentration (EC50) of CuO NPs to E. splendens was about 480 mg/L, implying the tolerance of E. splendens to CuO NPs. The Cu content in the shoots treated with 1000 mg/L CuO NPs was much higher than those exposed to the comparable 0.5 mg/L soluble Cu and CuO bulk particles. CuO NPs-like deposits were found in the root cells and leaf cells. Cu K-edge X-ray absorption near-edge structure analysis further revealed that the accumulated Cu species existed predominantly as CuO NPs in the plant tissues. All these results suggested that CuO NPs can be absorbed by the roots and translocated to the shoots in E. splendens.
Copper chaperones compose a specific class of proteins assuring safe handling and specific delivery of potentially harmful copper ions to a variety of essential copper proteins. Copper chaperones are ...structurally heterogeneous and can exist in multiple metal-loaded as well as oligomeric forms. Moreover, many copper chaperones can exist in various oxidative states and participate in redox catalysis, connected with their functioning. This review is focused on the analysis of the structural and functional properties of copper chaperones and their partners, which allowed us to define specific regulatory principles in copper metabolism connected with copper-induced conformational control of copper proteins.
Copper sulfides and copper selenides have recently been reported as new and promising low‐cost and environmentally friendly thermoelectric materials. Here, it is shown that these materials have ...actually been studied for more than 190 years and the absence of commercial thermoelectric modules based on them stems from some major intrinsic issues related to these chalcogenides. Further development of these semiconductors will require addressing and solving these problems before large scale utilization can be considered.
Copper sulfides and copper selenides have recently been reported as new and promising low‐cost and environmentally friendly thermoelectric materials. It is shown that these materials have actually been studied for more than 190 years. The absence of commercial thermoelectric modules based on them stems from some major intrinsic issues related to these chalcogenides. Further developing these semiconductors will require addressing and solving these problems before large scale utilization can be considered.
Much of the world's economic copper resources are hosted in porphyry copper deposits (PCDs), shallow level magmatic intrusions associated mostly with thick (>45km) magmatic arcs, such as mature ...island arcs and continental arcs. However, a well-known, but unresolved paradox, is that arc magmas traversing thick crust, particularly in continental arcs, are generally depleted in Cu whereas in island arcs, where PCDs are less common, magmas become enriched in Cu. Here, we show that the formation of PCDs requires a complex sequence of intra-crustal magmatic processes, from the lower crust to the upper crust. PCDs form when the crust becomes thick (>45km) enough to crystallize garnet. Garnet fractionation depletes Fe from the magma, which drives sulfide segregation and removal of most of the magma's Cu into the lower crust, leaving only small amounts of Cu in the residual magma to make PCDs. However, because garnet is depleted in ferric iron, the remaining Fe in the magma becomes progressively oxidized, which eventually oxidizes sulfide to sulfate, thereby releasing sulfide bound Cu from the magma into solution. This auto-oxidation of the magma, made possible by deep-seated garnet fractionation, increases the ability of endogenic magmatic fluids to self-scavenge Cu from large volumes of otherwise Cu-poor magmas and then transport and concentrate Cu to the tops of magmatic bodies. Examination of the occurrence of PCDs in the central Andes shows that ore formation occurs when continental arcs reach their maximum thickness (>60km), just before the termination of magmatism.
In continental arcs, where oceanic lithosphere subducts beneath continental lithosphere, intracrustal magmatic differentiation likely plays a dominant role in controlling the composition of magmas. Of particular interest are the occurrence of Cu-porphyry systems, which are typically found late in the “life-cycle” of an arc when arc crustal thickness is the greatest. During this time, deep-seated fractionation of garnet-rich cumulates, known as arclogites, results in oxidation of the residual magma, increasing the scavenging power of late stage magmatic fluids and the possibility of making Cu-porphyries.
•Copper porphyries form in continental arcs during maximum crustal thickness.•Deep crustal fractionation is essential for making Cu-porphyries.•Garnet fractionation increases Cu scavenging power of residual magmatic fluids.•Cu-porphyries derive from Cu-poor plutons.•The major repository of Cu in lower crustal sulfides.
PDF
