Eukaryotic Cell
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplemental material
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 Campbell, L. T.
Right arrow Articles by Heitman, J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Campbell, L. T.
Right arrow Articles by Heitman, J.

 Previous Article  |  Next Article 

Eukaryotic Cell, August 2005, p. 1410-1419, Vol. 4, No. 8
1535-9778/05/$08.00+0     doi:10.1128/EC.4.8.1410-1419.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.

Clinical and Environmental Isolates of Cryptococcus gattii from Australia That Retain Sexual Fecundity{dagger}

Leona T. Campbell,1,{ddagger} James A. Fraser,2,3,{ddagger} Connie B. Nichols,2,3 Fred S. Dietrich,2 Dee Carter,1 and Joseph Heitman2,3*

Division of Microbiology, School of Molecular and Microbial Biosciences, University of Sydney, Sydney 2006, Australia,1 Department of Molecular Genetics and Microbiology,2 Howard Hughes Medical Institute, Duke University, Durham, North Carolina 277103

Received 7 April 2005/ Accepted 23 May 2005

Cryptococcus gattii is a primary pathogenic yeast that causes disease in both animals and humans. It is closely related to Cryptococcus neoformans and diverged from a common ancestor ~40 million years ago. While C. gattii has a characterized sexual cycle dependent upon a dimorphic region of the genome known as the MAT locus, mating has rarely been observed in this species. In this study, we identify for the first time clinical (both human and veterinary) and environmental isolates from Australia that retain sexual fecundity. A collection of 120 isolates from a variety of geographic locations was analyzed for molecular type, mating type, and the ability to develop mating structures when cocultured with fertile tester strains. Nine isolates produced dikaryotic filaments with paired nuclei, fused clamp connections, and basidiospores. DNA sequence analysis of three genes (URA5, the MAT{alpha}-specific SXI1{alpha} gene, and the MATa-specific SXI2a gene) revealed little or no variability in URA5 and SXI2a, respectively. However across the 108 MAT{alpha} strains sequenced, the SXI1{alpha} gene was found to exist as 11 different alleles. Phylogenetic analysis found most variation to occur in the more fertile genotypes. Although some lineages of Australian C. gattii have retained the ability to mate, the majority of isolates were sterile, suggesting that asexuality is the dominant mode of propagation in these populations.

* Corresponding author. Mailing address: Duke University Medical Center, 322 CARL Building, Research Drive, Durham, NC 27710. Phone: (919) 689-2824. Fax: (919) 689-5458. E-mail: heitm001{at}duke.edu.

{dagger} Supplemental material for this article may be found at http://ec.asm.org/.

{ddagger} L.T.C. and J.A.F. contributed equally to this work.

Eukaryotic Cell, August 2005, p. 1410-1419, Vol. 4, No. 8
1535-9778/05/$08.00+0     doi:10.1128/EC.4.8.1410-1419.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:



HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Appl. Environ. Microbiol. Infect. Immun. J. Bacteriol.
Mol. Cell Biol. Microbiol. Mol. Biol. Rev. ALL ASM JOURNALS
Copyright © 2005 by the American Society for Microbiology.