Copper insertion

Figure 3.9 Proposed mechanism of copper insertion into SOD1 by its metallochaperone CCS. (From Culotta et al., 2006. Copyright 2006, with permission from Elsevier.)...

As we will discuss later, in Chapter 8, free copper levels are extremely low within cells because the copper is bound to a family of metallochaperones, which are subsequently involved in the incorporation of copper into copper-containing proteins. The mechanism proposed for copper insertion into the Cu/Zn superoxide dismutase, SOD1, is presented in Figure 3.9. The copper chaperone, CCS, acquires copper as Cu+ from a copper transporter and then docks with the reduced dithiol form of SOD1 (Steps I and II) to give a docked... 

EDTA (Ki 1.6 X 10 M) (Rae et al., 1999). The primary conclusion derived from these studies is that in the presence of copper scavengers, Cu(I)yCCS activates ySODl hut Cu(l)GSH and CUSO4 cannot. Importantly, the copper insertion event likely occurs with direct transfer of the metal ion from yCCS to the ySODl, as copper ions that might possibly dissociate from the yCCS or GSH donor molecules are rapidly sequestered by the BCS competitor molecule, which is present in 20-fold excess over the copper donor molecules under these assay conditions. This in turn suggests that specific protein-protein interactions are involved in the recognition of ySODl by yCCS (Rae et al., 1999). 

Metalloprotein protein that binds a specific metal ion and requires that metal ion for proper function Metal transporter transmembrane protein responsible for the translocation of metal ions across a lipid bilayer MTMl mitochondrial inner membrane transporter needed for activating SOD2 with manganese SCO Copper carrying molecule, possibly the copper chaperone or copper insertion factor for cytochrome oxidase SMF2 intracellular metal transporter essential for manganese trafficking... 

A number of copper requiring enzymes are located at the cell surface or are exported into the extracellular milieu. Examples of such secretory Cu-enzymes include copper requiring ferroxidases that fimction in iron transport (e g. ceruloplasmin, CP), enzymes for neurotransmission (peptidyl amidating enzyme and dopamine hydroxylase), an extracellular superoxide dismutase (SOD) that fimctions in antioxidant defense and enzymes for formation of connective tissue (lysyl oxidase), and pigments (tyrosinase) (reviewed in ). En route to their designated location, each of these enzymes passes through a specialized compartment of the late Golgi where copper insertion takes place. 

DLC films can also be used as dielectric layers for thermal management systems. In this case, the DLC film is coated on copper inserts used as heat transfer devices in multichip... 

Hydrogenation is effected in a steel shaking autoclave with a copper insert of 500 ml capacity. The ketone or aldehyde (0.25 mole) and copper chromite catalyst (4g)184 are introduced. For hydroxy aldehydes, anhydrous methanol (100 ml) is also added, to prevent formation of resinous products. For aromatic ketones the initial pressure of hydrogen is 300-340 atm, but for hydroxy aldehydes and hydroxy ketones 220-240 atm suffice. When alcohol is used, the temperature is kept at 200-250° until the pressure remains constant when no alcohol is used, a temperature of 180-195° suffices for reduction to the hydrocarbon. When hydrogenation is complete, the mixture is washed from the vessel with methanol or benzene, filtered from the catalyst, and worked up as usual. 

SCO Copper carrying molecule, possibly the copper chaperone or copper insertion factor for cytochrome oxidase SMF2 intracellular metal transporter essential for manganese trafficking... 

Injection molds are usually made from high quality tool-grade steel. They may include beryllium copper inserts to improve heat transfer rates for more rapid cooling. Molds are quite expensive, and often contain wear plates that can easily be replaced, so that the molds can be more easily refurbished and have a longer life. 

Br on Pt(l 11) was monitored in a solution free of copper (insert of Figure 6). It should also be noted that in potential range where an ordered (4 x 4) bilayer structure was observed by ex situ LEED there is an increase in the surface coverage by Br versus the Pt surface in the Cu free solution. The true nature of this structure, however, can only be resolved by SXS measurements, as we discuss below. 

For LaCoi cCu c03, a paper [25] examines the effect of the partial substitution on the B-site (Co) by Cu in LaCoOs synthesized by the citrate method, at various calcination temperatures, for different values of (0< <0.3). By XRD, it is demonstrated that the substitution of Co by Cu is possible in a rhombohedral cell with a linear increase of the lattice parameters and of the cell volume (according to Vegard s law) with increase of copper insertion. 

Thus, in valve-regulated lead-acid batteries electrolyte- and gas-tight pole bushings are a must, and vented batteries allow the use of copper inserts and screws for cell and battery connectors and thus install the battery as usual in electro technics. 

Stationary batteries in plastic cases are sealed with epoxy glues, with solvent cement, or (for PVC copolymer cases and covers) with a thermal seal. Terminals are cast or welded on. Some very large stationary and traction cells are made so that coolant can be circulated through the terminals, and others are made with terminals with copper inserts for increased... 

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