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 Giles, S. S.
Right arrow Articles by Perfect, J. R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Giles, S. S.
Right arrow Articles by Perfect, J. R.

Next Article 

Eukaryotic Cell, September 2006, p. 1447-1459, Vol. 5, No. 9
1535-9778/06/$08.00+0     doi:10.1128/EC.00098-06
Copyright © 2006, American Society for Microbiology. All Rights Reserved.

The Cryptococcus neoformans Catalase Gene Family and Its Role in Antioxidant Defense

Steven S. Giles,3 Jason E. Stajich,2,4 Connie Nichols,1 Quincy D. Gerrald,1 J. Andrew Alspaugh,1,2 Fred Dietrich,2,4 and John R. Perfect1,2*

Departments of Medicine,1 Molecular Genetics and Microbiology,2 Cell Biology,3 Institute of Genome Sciences and Policy, Duke University Medical Center, Durham, North Carolina4

Received 6 April 2006/ Accepted 20 June 2006

In the present study, we sought to elucidate the contribution of the Cryptococcus neoformans catalase gene family to antioxidant defense. We employed bioinformatics techniques to identify four members of the C. neoformans catalase gene family and created mutants lacking single or multiple catalase genes. Based on a phylogenetic analysis, CAT1 and CAT3 encode putative spore-specific catalases, CAT2 encodes a putative peroxisomal catalase, and CAT4 encodes a putative cytosolic catalase. Only Cat1 exhibited detectable biochemical activity in vitro, and Cat1 activity was constitutive in the yeast form of this organism. Although they were predicted to be important in spores, neither CAT1 nor CAT3 was essential for mating or spore viability. Consistent with previous studies of Saccharomyces cerevisiae, the single (cat1, cat2, cat3, and cat4) and quadruple (cat1 cat2 cat3 cat4) catalase mutant strains exhibited no oxidative-stress phenotypes under conditions in which either exogenous or endogenous levels of reactive oxygen species were elevated. In addition, there were no significant differences in the mean times to mortality between groups of mice infected with C. neoformans catalase mutant strains (the cat1 and cat1 cat2 cat3 cat4 mutants) and those infected with wild-type strain H99. We conclude from the results of this study that C. neoformans possesses a robust antioxidant system, composed of functionally overlapping and compensatory components that provide protection against endogenous and exogenous oxidative stresses.

* Corresponding author. Mailing address: Department of Medicine and Microbiology, Duke University Medical Center, Box 3353, Durham, NC 27710. Phone: (919) 684-4016. Fax: (919) 684-8902. E-mail: Perfe001{at}mc.duke.edu.

Eukaryotic Cell, September 2006, p. 1447-1459, Vol. 5, No. 9
1535-9778/06/$08.00+0     doi:10.1128/EC.00098-06
Copyright © 2006, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Giles, S. S., Dagenais, T. R. T., Botts, M. R., Keller, N. P., Hull, C. M. (2009). Elucidating the Pathogenesis of Spores from the Human Fungal Pathogen Cryptococcus neoformans. Infect. Immun. 77: 3491-3500 [Abstract] [Full Text]  
  • Rodrigues, M. L., Nakayasu, E. S., Oliveira, D. L., Nimrichter, L., Nosanchuk, J. D., Almeida, I. C., Casadevall, A. (2008). Extracellular Vesicles Produced by Cryptococcus neoformans Contain Protein Components Associated with Virulence. Eukaryot Cell 7: 58-67 [Abstract] [Full Text]  
  • Idnurm, A., Giles, S. S., Perfect, J. R., Heitman, J. (2007). Peroxisome Function Regulates Growth on Glucose in the Basidiomycete Fungus Cryptococcus neoformans. Eukaryot Cell 6: 60-72 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»