Copper-zinc superoxide dismutase yeast

Gralla EB, Thiele DJ, Silar P, Valentine JS. ACE1, a copper-dependent transcription factor, activates expression of the yeast copper, zinc superoxide dismutase gene. Proc Natl Acad Sci USA 88 8558-8562, 1991. 

Lu, Y. Roe, J. A. Gralla, E. B. Valentine, J. S. Metalloprotein ligand redesign characterization of copper-cysteinate proteins derived from yeast copper-zinc superoxide dismutase. In Bioinorganic Chemistry of Copper Karlin, K. D. Tyeklar, Z., Eds. Chapman and Hall New York, 1993 pp 64-77. 

Tamai KT, Gralla EB, Ellerby LM, Valentine JS, Thiele DJ (1993) Yeast and mammalian metallothioneins functionally substitute for yeast copper-zinc superoxide dismutase. Proc Natl Acad Sci USA 90 8013-8017... 

Fig. 1. Schematic overview of copper trafficking and homeostasis inside the yeast cell. The actions of Mad and Ace 1, copper-dependent metalloregulatory transcription factors, control the production of copper import [copper transporter (Ctr) and reductase (Fre)] and detoxification/sequestration [metallothionein (MT)] machineries, respectively. Three chaperone-mediated delivery pathways are shown. Atxl shuttles Cu(I) to the secretory pathway P-type ATPase Ccc2 (right). CCS delivers Cu(I) to the cytoplasmic enzyme copper-zinc superoxide dismutase (SOD) (left). Coxl7 shuttles Cu(I) to cytochrome c oxidase (CCO) in the mitochondria (bottom). Mitochondrial proteins Scol and Sco2 may also play a role in copper delivery to the CuA and CuB sites of CCO. Copper metabolism and iron metabolism are linked through the actions of Fet3, a copper-containing ferroxidase required to bring iron into the cell (lower right) (see text).

These are (1) the copper-zinc superoxide dismutases, CuZnSOD, °° ° found in almost all eukaryotic cells and a very few prokaryotes, and (2) the manganese and iron superoxide dismutases, MnSOD and FeSOD, the former found in the mitochondria of eukaryotic cells, and both found in many prokaryotes. Recent studies of bacterial and yeast mutants that were engineered to contain no superoxide dismutases demonstrated that the cells were unusually sensitive... 

Superoxide dismutases have been isolated from a wide variety of eukaryotes including yeast, wheat germ, garden peas, chicken liver and erythrocytes. These enzymes contain copper and zinc. Copper containing proteins which also display this catalytic activity had been isolated from blood, brain and liver tissues many years previously and were known as erythrocuprein, cerebrocuprein and hepatocuprein. 

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