Copper transporters

NOTE For supercritical boilers, particular care must be given to controlling copper (transported in the condensate and resulting from corrosion of condenser admiralty brass) because it tends to be very troublesome, laying down metal and oxides in the turbine. 

NOTE Probably the most important junction of oxygen scavengers is, in reality, the ability to passivate boiler steel. In recognition of this, today most novel oxygen scavenger trials try to identify, not merely comparative oxygen reaction rates, but more importantly, the reduction in iron and copper transport rates through the boiler system. In other words, they seek to optimize the passivation of boiler surfaces and other system components. 

Harris ED Cellular copper transport and metabolism. Annu Rev Nutr 2000 20 291. 

Caeruloplasmin (Cp) is an acute phase glycoprotein with a copper transport function. At least 90% of total plasma copper is bound to Cp with the remaining 10% associated with albumin, histidine and small peptides. Lipid peroxidation requires the presence of trace amounts of transition metals and the copper-containing active site of Cp endows it with antioxidant capacity... 

Franke, S., Grass, G., Rensing, C., and Nies, D.H., Molecular analysis of the copper-transporting efflux system CusCFBA of Escherichia coli, J Bacteriol, 185 (13), 3804-3812, 2003. 

Figure 4.5 Fet3p and copper homeostasis. Defects in the plasma membrane transporters Ctrl and Ctr3, the cytosolic copper chaperone Atxlp, or the vesicular copper transporter Ccc2p affect Fet3p activity. Reprinted from Askwith and Kaplan, 1998. Copyright (1998), with permission from Elsevier Science.

Copper is associated with two important life-threatening diseases in man, the pathologies of both being due to defective intracellular copper transport. Menke s disease is characterized by progressive cerebral degeneration, essentially due to insufficient copper absorption, and Wilson s disease is due to excessive copper accumulation in liver, accompanied by liver disease and haemolytic crises. 

EGS and sulfo-EGS also have been used to study the surface loop motion in FepA (Scott et al., 2002), to characterize the high affinity copper transporter in Saccharomyces cerevi-siae (Pena et al., 2000), and in the study of protein interactions and large protein complexes (Petrotchenko et al., 2005(2005 a or b ). 

Pena, M.M.O., Puig, S., and Thiele, D.J. (2000) Characterization of the Saccharomyces cerevisiae high affinity copper transporter Ctr3./. Biol. Chem. 275, 33244-33251. 

ATP-dependent Ca2+ pumps and Na+,Ca2+ antiporters act in concert to maintain a low concentration of free cytosolic Ca2+ 79 The uniquely high resolution structural data available for the SERCAla Ca2+ pump illuminates the structure of all P-type transporters 81 P-type copper transporters are important for neural function 82... 

P-type copper transporters are important for neural function. Wilson s and Menke s diseases have major neurological components (Ch. 45). The Wilson s disease gene codes for a transporter, expressed chiefly in liver, that probably functions in Cu2+ excretion. The Menke s disease gene codes for a closely related transporter that regulates intestinal Cu2+ absorption [32],... 

The disease results from mutations within the ATP7B gene on the short arm of chromosome 13 [23, 24]. This gene encodes a protein which appears to be involved in copper transport coupled with the synthesis of ceruloplasmin and other cuproproteins. 

Mercer, J. F. The molecular basis of copper-transport diseases. Trends Mol. Med. 7 64-69, 2001. 

The copper transport function of ceruloplasmin has been documented in several reviews (e.g. see refs. 15, 42, 43) and a transport function established. The turnover of ceruloplasmin allows copper ions to move from the major sites of ceruloplasmin synthesis in liver cells [44,45] to peripheral tissues for incorporation into copper-dependent enzymes [46,47], but transport mechanisms may also be active which involve copper atoms in the intact protein. However, the complexity of the protein has made it difficult to determine which, if any, of the six integral copper atoms are involved in copper delivery or whether there exist additional... 

Figure 7.26 Copper transport pathways. (Adapted with permission from Sarkar, B. Chem. Rev., 1999, 99(9), 2535-2544. Copyright 1999, American Chemical Society.)...

---