JB
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Riggle, P. J.
Right arrow Articles by Kumamoto, C. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Riggle, P. J.
Right arrow Articles by Kumamoto, C. A.

 Previous Article  |  Next Article 

Journal of Bacteriology, September 2000, p. 4899-4905, Vol. 182, No. 17
0021-9193/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.

Role of a Candida albicans P1-Type ATPase in Resistance to Copper and Silver Ion Toxicity

Perry J. Riggle and Carol A. Kumamoto*

Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111

Received 21 March 2000/Accepted 6 June 2000

Copper ion homeostasis is complicated in that copper is an essential element needed for a variety of cellular processes but is toxic at excess levels. To identify Candida albicans genes that are involved in resistance to copper ion toxicity, a library containing inserts of C. albicans genomic DNA was used to complement the copper sensitivity phenotype of a Saccharomyces cerevisiae cup1Delta strain that is unable to produce Cup1p, a metallothionein (MT) responsible for high-level copper ion resistance. A P1-type ATPase (CPx type) that is closely related to the human Menkes and Wilson disease proteins was cloned. The gene encoding this pump was termed CRD1 (for copper resistance determinant). A gene encoding a 76-amino-acid MT similar to higher eukaryotic MTs in structure was also cloned, and the gene was termed CRD2. Transcription of the CRD1 gene was found to increase upon growth with increasing copper levels, while the CRD2 mRNA was expressed at a constant level. Strains with the CRD1 gene disrupted were extremely sensitive to exogenous copper and failed to grow in medium containing 100 µM CuSO4. These crd1 strains also exhibited increased sensitivity to silver and cadmium, indicating that Crd1p is somewhat promiscuous with respect to metal ion transport. Although strains with the CRD2 gene disrupted showed reduced growth rate with increasing copper concentration, the crd2 mutants eventually attained wild-type levels of growth, demonstrating that CRD2 is less important for resistance to copper ion toxicity. Crd1p is the first example of a eukaryotic copper pump that provides the primary source of cellular copper resistance, and its ability to confer silver resistance may enhance the prevalence of C. albicans as a nosocomial pathogen.

* Corresponding author. Mailing address: Department of Molecular Biology and Microbiology, Tufts University School of Medicine, 136 Harrison Ave., Boston, MA 02111. Phone: (617) 636-0404. Fax: (617) 636-0337. E-mail: carol.kumamoto{at}tufts.edu.

Journal of Bacteriology, September 2000, p. 4899-4905, Vol. 182, No. 17
0021-9193/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
Appl. Environ. Microbiol. Infect. Immun. Eukaryot. Cell
Mol. Cell. Biol. J. Virol. Microbiol. Mol. Biol. Rev.
ALL ASM JOURNALS

Copyright © 2000 by the American Society for Microbiology. All rights reserved.