HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Ren, P. Articles by Hanes, S. D. Search for Related Content PubMed PubMed Citation Articles by Ren, P. Articles by Hanes, S. D. Agricola Articles by Ren, P. Articles by Hanes, S. D.

The Ess1 prolyl isomerase is dispensable for growth but required for virulence in Cryptococcus neoformans

¹ Molecular Genetics Program, Wadsworth Center, New York State Department of Health, State University of New York, Albany, NY 12208, USA
² Mycology Laboratory, Wadsworth Center, New York State Department of Health, State University of New York, Albany, NY 12208, USA
³ Department of Biomedical Sciences, School of Public Health, State University of New York, Albany, NY 12208, USA

Correspondence
Steven D. Hanes
hanes{at}wadsworth.org

Cryptococcus neoformans is an important human fungal pathogen that also serves as a model for studies of fungal pathogenesis. C. neoformans contains several genes encoding peptidyl-prolyl cis/trans isomerases (PPIases), enzymes that catalyse changes in the folding and conformation of target proteins. Three distinct classes of PPIases have been identified: cyclophilins, FK506-binding proteins (FKBPs) and parvulins. This paper reports the cloning and characterization of ESS1, which is believed to be the first (and probably only) parvulin-class PPIase in C. neoformans. It is shown that ESS1 from C. neoformans is structurally and functionally homologous to ESS1 from Saccharomyces cerevisiae, which encodes an essential PPIase that interacts with RNA polymerase II and plays a role in transcription. In C. neoformans, ESS1 was found to be dispensable for growth, haploid fruiting and capsule formation. However, ESS1 was required for virulence in a murine model of cryptococcosis. Loss of virulence might have been due to the defects in melanin and urease production observed in ess1 mutants, or to defects in transcription of as-yet-unidentified virulence genes. The fact that Ess1 is not essential in C. neoformans suggests that, in this organism, some of its functions might be subsumed by other prolyl isomerases, in particular, cyclophilins Cpa1 or Cpa2. This is supported by the finding that ess1 mutants were hypersensitive to cyclosporin A. C. neoformans might therefore be a useful organism in which to investigate crosstalk among different families of prolyl isomerases.

The GenBank/EMBL/DDBJ accession number for the sequence reported in this paper is AF533511.

This article has been cited by other articles:

				B. Henderson, E. Allan, and A. R. M. Coates Stress Wars: the Direct Role of Host and Bacterial Molecular Chaperones in Bacterial Infection Infect. Immun., July 1, 2006; 74(7): 3693 - 3706. [Full Text] [PDF]