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 Other Versions of this Article:
EC.00307-07v1
7/4/602    most recent
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 Rodrigues, M. L.
Right arrow Articles by Casadevall, A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Rodrigues, M. L.
Right arrow Articles by Casadevall, A.

 Previous Article  |  Next Article 

Eukaryotic Cell, April 2008, p. 602-609, Vol. 7, No. 4
1535-9778/08/$08.00+0     doi:10.1128/EC.00307-07
Copyright © 2008, American Society for Microbiology. All Rights Reserved.

Binding of the Wheat Germ Lectin to Cryptococcus neoformans Suggests an Association of Chitinlike Structures with Yeast Budding and Capsular Glucuronoxylomannan{triangledown} ,{dagger}

Marcio L. Rodrigues,1* Mauricio Alvarez,2 Fernanda L. Fonseca,1 and Arturo Casadevall2,3*

Laboratório de Estudos Integrados em Bioquímica Microbiana, Instituto de Microbiologia Professor Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-590, Brazil,1 Department of Microbiology and Immunology,2 Division of Infectious Diseases of the Department of Medicine, Albert Einstein College of Medicine, 1300 Morris Park Ave., Bronx, New York 104613

Received 19 August 2007/ Accepted 11 November 2007

The capsule of Cryptococcus neoformans is a complex structure whose assembly requires intermolecular interactions to connect its components into an organized structure. In this study, we demonstrated that the wheat germ agglutinin (WGA), which binds to sialic acids and β-1,4-N-acetylglucosamine (GlcNAc) oligomers, can also bind to cryptococcal capsular structures. Confocal microscopy demonstrated that these structures form round or hooklike projections linking the capsule to the cell wall, as well as capsule-associated structures during yeast budding. Chemical analysis of capsular extracts by gas chromatography coupled to mass spectrometry and high-pH anion-exchange chromatography suggested that the molecules recognized by WGA were firmly associated with the cell wall. Enzymatic treatment, competition assays, and staining with chemically modified WGA revealed that GlcNAc oligomers, but not sialic acids, were the molecules recognized by the lectin. Accordingly, treatment of C. neoformans cells with chitinase released glucuronoxylomannan (GXM) from the cell surface and reduced the capsule size. Chitinase-treated acapsular cells bound soluble GXM in a modified pattern. These results indicate an association of chitin-derived structures with GXM and budding in C. neoformans, which may represent a new mechanism by which the capsular polysaccharide interacts with the cell wall and is rearranged during replication.

* Corresponding author. Mailing address for Marcio L. Rodrigues: Instituto de Microbiologia Professor Paulo de Góes, Universidade Federal do Rio de Janeiro, 21941590, RJ, Brazil. Phone: 55 21 2562 6740. Fax: 55 21 2560 8344. E-mail: marcio{at}micro.ufrj.br. Mailing address for Arturo Casadevall: Department of Microbiology and Immunology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461. Phone: (718) 430-2215. Fax: (718) 430-8968. E-mail: casadeva{at}aecom.yu.edu

{triangledown} Published ahead of print on 26 November 2007.

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

Eukaryotic Cell, April 2008, p. 602-609, Vol. 7, No. 4
1535-9778/08/$08.00+0     doi:10.1128/EC.00307-07
Copyright © 2008, 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 © 2008 by the American Society for Microbiology.