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 Weig, M. Articles by De Groot, P. W. J. Search for Related Content PubMed PubMed Citation Articles by Weig, M. Articles by De Groot, P. W. J. Agricola Articles by Weig, M. Articles by De Groot, P. W. J.

Systematic identification in silico of covalently bound cell wall proteins and analysis of protein–polysaccharide linkages of the human pathogen Candida glabrata

¹ Institute of Medical Microbiology and National Reference Center for Systemic Mycoses, University of Göttingen, Germany
² GBF, Braunschweig, Germany
³ SILS-Microbiology, University of Amsterdam, The Netherlands
⁴ SILS-Biomacromolecular Mass Spectrometry, University of Amsterdam, The Netherlands

Correspondence
Piet W. J. de Groot
pgroot{at}science.uva.nl

Candida glabrata is an important cause of systemic candidiasis in humans. This paper reports a systematic analysis of the putative glycosylphosphatidylinositol-modified (GPI) proteins of C. glabrata, a large part of which are covalently bound to the cell wall glucan network and the remainder of which are retained in the plasma membrane, and of cell wall proteins (CWPs) which are covalently bound in a mild-alkali-sensitive manner. In silico genomic analysis revealed 106 putative GPI proteins. Fifty-one of these GPI proteins could be categorized as adhesive proteins, potentially implicated in fungus–host interactions or biofilm formation during the development of fungal infections. Eleven proteins belonged to well-known GPI protein families of glycoside hydrolases, probably involved in cell wall expansion and remodelling during growth. Other identified GPI proteins included phospholipases, aspartic proteases, homologues of ScEcm33p and ScKre1p, and structural CWPs. Interestingly, the GPI algorithm predicted three orthologues of an abundant CWP in S. cerevisiae, Cwp1p, which is absent in Candida albicans. To evaluate the in silico predictions, isolated cell walls were extracted using HF-pyridine, which specifically cleaves phosphodiester bonds, to release GPI-CWPs. Immunological analysis of the extract using one-dimensional SDS-PAGE and anti-ScCwp1p antiserum indicated the presence of a Cwp1p homologue in C. glabrata cell walls. Further analysis by two-dimensional gel electrophoresis and electrospray ionization tandem mass spectrometry (ESI-MS/MS) confirmed the presence of two of the predicted Cwp1p proteins, Cwp1.1p and Cwp1.2p. Crh1p, a putative 1,3--glucan remodelling enzyme, was also identified. In silico genomic analysis further revealed five putative Pir proteins (Pir1–5p) and five members of the Bgl2 glycoside hydrolase family 17, belonging to a class of putative CWPs that can be extracted with NaOH. Immunological analysis of mild-alkali-extracted CWPs showed the presence of a ScPir2p homologue. Together, these experimental data and in silico predictions represent the first systematic analysis of the C. glabrata cell wall proteome.

This article has been cited by other articles:

				J. E. Coronado, S. Mneimneh, S. L. Epstein, W.-G. Qiu, and P. N. Lipke Conserved Processes and Lineage-Specific Proteins in Fungal Cell Wall Evolution Eukaryot. Cell, December 1, 2007; 6(12): 2269 - 2277. [Abstract] [Full Text] [PDF]

				M. L. Richard and A. Plaine Comprehensive Analysis of Glycosylphosphatidylinositol-Anchored Proteins in Candida albicans Eukaryot. Cell, February 1, 2007; 6(2): 119 - 133. [Full Text] [PDF]

				A. Albrecht, A. Felk, I. Pichova, J. R. Naglik, M. Schaller, P. de Groot, D. MacCallum, F. C. Odds, W. Schafer, F. Klis, et al. Glycosylphosphatidylinositol-anchored Proteases of Candida albicans Target Proteins Necessary for Both Cellular Processes and Host-Pathogen Interactions J. Biol. Chem., January 13, 2006; 281(2): 688 - 694. [Abstract] [Full Text] [PDF]

				Q. Y. Yin, P. W. J. de Groot, H. L. Dekker, L. de Jong, F. M. Klis, and C. G. de Koster Comprehensive Proteomic Analysis of Saccharomyces cerevisiae Cell Walls: IDENTIFICATION OF PROTEINS COVALENTLY ATTACHED VIA GLYCOSYLPHOSPHATIDYLINOSITOL REMNANTS OR MILD ALKALI-SENSITIVE LINKAGES J. Biol. Chem., May 27, 2005; 280(21): 20894 - 20901. [Abstract] [Full Text] [PDF]

				A. Duran and C. Nombela Fungal cell wall biogenesis: building a dynamic interface with the environment Microbiology, October 1, 2004; 150(10): 3099 - 3103. [Full Text] [PDF]