The Saccharomyces cerevisiae cell surface is endowed with some relevant technological properties, notably antimicrobial and biosorption activities. For these purposes, yeasts are usually processed and packaged in an 'autolysed/dried' formula, which may have some impacts on cell surface properties. In this report, we showed using a combination of biochemical, biophysical and molecular methods th...

A number of isolates of Saccharomyces cerevisiae have been associated with disease in immunocompromised individuals. Such isolates display a variety of characteristics that enable colonization and persistence in the host. The aim of the work presented here was to establish whether clinical isolates of S. cerevisiae were capable of adhering to epithelial tissue. Adherence to host tissue has been...

An antigen (Ag), as defined by reactivity with a monoclonal antibody (mAb 10G), was found on the cell wall surface and on the plasma membrane of Candida albicans yeast cells (Li, R. K., and Cutler, J. E. (1991) J. Gen. Microbiol. 137, 455-464). The 10G Ag from the cell surface location was solubilized by treatment with beta-mercaptoethanol and Zymolyase. Antigenic activity of the extract was lo...

The cell surface of Candida albicans is enriched in highly glycosylated mannoproteins that are involved in the interaction with the host tissues. N glycosylation is a posttranslational modification that is initiated in the endoplasmic reticulum (ER), where the Glc(3)Man(9)GlcNAc(2) N-glycan is processed by alpha-glucosidases I and II and alpha1,2-mannosidase to generate Man(8)GlcNAc(2). This N-...

The major virulence factor of Cryptococcus neoformans is its capsular polysaccharide, which is also released into tissues. The shed polysaccharide is composed of glucuronoxylomannan, galactoxylomannan (GalXM), and mannoproteins. In a previous study, we demonstrated a direct interaction of purified soluble GalXM with T cells that induced their apoptosis. In this study, we focus on the mechanisms...

The organization of the components of the cell wall from Candida albicans was studied by means of sequential treatment with hot SDS, anhydrous ethylenediamine (EDA) and lytic enzymes, followed by chemical and microscopic analyses of the different separated fractions. The EDA-insoluble fraction retained the original morphology of the wall, which was destroyed by beta-glucanase, but not by chitin...

There is an immediate need for identification of new antifungal targets in opportunistic pathogenic fungi like Candida albicans. In the past, efforts have focused on synthesis of chitin and glucan, which confer mechanical strength and rigidity upon the cell wall. This paper describes the molecular analysis of CaMNT1, a gene involved in synthesis of mannoproteins, the third major class of macrom...

The budding yeast Saccharomyces cerevisiae has recently been described as an emerging opportunistic fungal pathogen. Fungal cell wall mannoproteins have been demonstrated to be involved in adhesion to inert surfaces and might be engaged in virulence. In this study, we observed four clinical isolates of S. cerevisiae with relatively hydrophobic cell surfaces. Yeast cell wall subproteome was eval...

Using appropriate yeast strains and exogenous acceptors, we have devised specific assays for four mannosyltransferase activities involved in biosynthesis of the carbohydrate outer chain of yeast mannoproteins. The assays utilize GDP-[14C]mannose as the donor and unlabeled oligosaccharides as the acceptors, the products being neutral radioactive oligosaccharides one mannose unit larger than the ...

Oropharyngeal candidiasis (OPC) remains a common opportunistic infection in HIV-infected patients. Candida albicans is the most frequent causative agent of OPC. However, non-albicans spp. are being increasingly isolated. Candidal cell wall proteins and mannoproteins play important roles in the biology and patogenesis of candidiasis. In the present study, we have analyzed the proteinaceous compo...