화학공학소재연구정보센터
Biochemical and Biophysical Research Communications, Vol.324, No.3, 1034-1040, 2004
A cloned prokaryotic Cd2+ P-type ATPase increases yeast sensitivity to Cd2+
CadA, the P1-type ATPase involved in Listeria monocytogenes resistance to Cd2+, was expressed in Saccharomyces cerevisiae and did just the opposite to what was expected, as it strikingly decreased the Cd2+ tolerance of these cells. Yeast cells expressing the non-functional mutant ASP(398)Ala could grow on selective medium containing up to 100 muM Cd2+ whereas those expressing the functional protein could not grow in the presence of 1 muM Cd2+. The CadA-GFP fusion protein was localized in the endoplasmic reticulum membrane, suggesting that yeast hyper-sensitivity was due to Cd2+ accumulation in the reticulum lumen. CadA is also known to transport Zn2+, but Zn2+ did not protect the cells against Cd poisoning. In the presence of 10 muM Cd2+ transformed yeasts survived by rapid loss of their expression vector. (C) 2004 Elsevier Inc. All rights reserved.