Saccharomyces cerevisiae copper

Saccharomyces cerevisiae 85 copper uptake 290 iron storage 100 zinc uptake 295 scandium 108 selenium xvii... 

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. 

Lehmann M, Riedel K, Adler K, Kunze G (2000) Amperometric measiuement of copper ions with a deputy substrate using a novel Saccharomyces cerevisiae sensor. Biosens Bioelectron 15 211-219... 

The metallothioneins have been found in several vertebrate species and in marine invertebrates.1452 Prinz and Weser purified a copper-containing metallothionein from Saccharomyces cerevisiae.1453 Another copper-binding protein was isolated from Neurospora crassa.1452 The first unequivocal demonstration of a metallothionein in a vascular plant was recently reported.1455 The amount of metallothionein in different species and tissues is variable. The concentration has been reported to increase up to 40-fold by the induction of its biosynthesis by certain metals such as cadmium or zinc. In new-born rat liver (one to four days old) the concentration of Zn- and Cu-metallothionein is 20 times that in 70-day-old adult rats.1456 There are several recent reports and reviews in this active area.1243,1467a k... 

Copper ligands of the recombinant tyrosinase from A. oryzae expressed in Saccharomyces cerevisiae or Escherichia coli were identified by site-directed mutagenesis [145],... 

Fig. 3. Mad activates the expression of three gene products involved in high-affinity copper ion uptake in Saccharomyces cerevisiae. Two genes encode Cu ion permeases Ctrl and Ctr3. The third is one of two metalloreductases that reduce Cu(II) ions prior to uptake. Mad is a transcriptional activator in Cu-deficient yeast cells.

Fig. 6. Occurrence of the CXCX(4 5) CXC consensus motif. CopY, cop operon repressor protein from Enterococcus hirae Mad, transcription factor for the Ctrl copper transporter of Saccharomyces cerevisiae AMTl, transcription factor for metal-lothionein from Candida albicans ACEl, transcription factor for metallothionein from Sa. cerevisiae Grisea, MACl orthologue of Podospora anserina MT-2 p-domain, N-terminal domain of human metallothionein-2.

Coxl7, an 8.1-kDa cysteine-rich protein, was the first copper chaperone to be identified. Saccharomyces cerevisiae harboring mutations in coxl 7 are respiratory deficient, a phenotype resulting from their inability to assemble a functional cytochrome c oxidase complex (Glerum et al., 1996a). coxl7 mutant yeast are, however, able to express all the subunits of the cytochrome c oxidase complex, indicating that the lesion must lie in a posttranslational step that is essential for assembly of the functional complex in the mitochondrial membrane. Unlike other cytochrome c... 

Fig. 14. Redox cycling in the uptake of copper and iron. The lower valent state species is substrate for uptake of copper and iron. The system in the yeast Saccharomyces cerevisiae is diagrammed. The Frel protein reduces environmental Cu " and Fe +. The cuprous ion is substrate for the copper permease, Ctrip. Fe + is substrate for Fet3p its oxidation to Fe + is an obligate step in iron uptake through Ftrlp. Exogenous ferric iron is not taken up by yeast cells unless it is cycled through the ferrireduction-ferrox-idation reactions catalyzed by Frelp and FetSp.

Eide, D. J., Bridgham, J. T, Zhao, Z., and Mattoon, J. R. (1993). The vacuolar H -ATPase of Saccharomyces cerevisiae is required for efficient copper detoxification, mitochondrial function, and iron metabolism. Mol. Gen. Genet. 241, 447 56. 

Hassett, R. E, Yuan, D. S., and Kosman, D. J. (1998). Spectral and kinetic properties of the Fet3 protein from Saccharomyces cerevisiae, a multinuclear copper ferroxidase enzyme. J. Biol. Chem. 273, 23274-23282. 

Machonkin, T. E., Quintanar, L., Palmer, A. E., Hassett, R., Severance, S., Kosman, D. J., and Solomon, E. I. (2001). Spectroscopy and reactivity of the type 1 copper site in Fet3p from Saccharomyces cerevisiae. Correlation of structure with reactivity in the multicopper oxidases./. Am. Chem. Soc. 123, 5507-5517. 

Cai, D. Y., and Klinman, J. P., 1994, Copper amine oxidase heterologous expression, purification and characterisation of an active enzyme in Saccharomyces cerevisiae. Biochemistry 33 7647n7653. 

Yeast mannan, commonly known as yeast gum by early workers, was first isolated in a pure form by Salkowski. It was extracted from pressed bakers yeast (Saccharomyces cerevisiae) with hot, aqueous alkali, and separated from such contaminants as glycogen through the insoluble, copper complex formed with Fehling solution. Mundkur has presented evidence indicating that a layer of mannan... 

Regulation of copper uptake has been studied in most detail in the yeast Saccharomyces cerevisiae. Uptake of Cu + is similar to fhaf of Fe. The same plasma membrane reducfase system, consisting of proteins Frelp and Fre2p (encoded by genes FRE1 and FRET), acts to reduce both Fe + and These two... 

While unicellular fungi do not require metal transport systems, multicellular fungi and plants most certainly do, and we consider their transport in plants, and then consider how metal ions are sequestered in storage compartments before addressing their homeostasis. Once again, we consider in turn these processes for iron, copper, and zinc. Since iron metabolism has been most intensively studied in Saccharomyces cerevisiae, of all the fungi, we will focus our attention on iron homeostatic mechanisms however, as the reader will see shortly, copper and zinc homeostasis have many similarities. 

FIGURE 8.15 Copper homeostasis in Saccharomyces cerevisiae. (From Cobine, Pierrel, Winge, 2006. Copyright 2006, with permission from Elsevier.)... 

White, C., and Gadd, G. M. (1986). Uptake and cellular distribution of copper, cobalt and cadmium in strains of Saccharomyces cerevisiae cultured on elevated concentrations of these metals. FEMS Microbiol. Ecol. 38, 277-283. 

Lapinskas P, Ruis H, Culotta V. Regulation of Saccharomyces cerevisiae catalase gene expression by copper. Cur Genet 24 388-393, 1993. 

The accumulation of iron is dependent on its transport into the cell. Askwith and Kaplan (Chapter 4) discuss iron transport mechanisms in eukaryotic cells, developing models based on studies carried out in the yeast, Saccharomyces cerevisiae. These cells possess both siderophore-dependent and elemental iron transport systems. The latter system relies on cell surface ferrireductases to convert extracellular ferric chelates to ferrous iron, which can be transported through either a high or low affinity iron transport system. Studies on a high affinity ferrous iron transporter (FET3) revealed that the multicopper oxidase will oxidize ferrous to ferric iron, which is then mobilized across the membrane by a ferric transmembrane permease (Ftrlp). This is a highly specific transport system in yeast it only transports iron. In humans, the copper enzyme, ceruloplasmin, is responsible for the radical-free oxidase activity. This plasma protein oxidizes the ferrous iron that is excreted from cells into the transferrin-usable ferric form. 

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