Dimorphism in Candida albicans: Contribution of Mannoproteins to the Architecture of Yeast and Mycelial Cell Walls

Abstract

Wall mannoproteins of the two (yeast and mycelial) cellular forms of Candida albicans were solubilized by different agents. Boiling in 2% (w/v) SDS was the best method, as more than 70% of the total mannoprotein was extracted. Over 40 different bands (from 15 to 80 kDal) were detected on SDS-polyacrylamide gel electrophoresis of this material. The residual wall mannoproteins were released after enzymic (Zymolyase and endogenous wall P-glucanases) degradation of wall glucan, suggesting that they are covalently linked to this structural polymer. Four bands (of 160 kDal, 205 kDal and higher molecular mass) were observed in the material released from yeast walls but only the two smaller components were detected in the material obtained from mycelial walls. Moreover, the mannoproteins of high molecular mass, which are covalently linked in walls of normal cells, were not incorporated into walls of regenerating protoplasts, but non-covalently linked mannoproteins were retained from the beginning of the process.

Transcriptome and Biochemical Analysis Reveals That Suppression of GPI-Anchor Synthesis Leads to Autophagy and Possible Necroptosis in Aspergillus fumigatus

“…After digestion, HCl was evaporated and the residues were dissolved in 0.2 ml distilled water [25]–[27]. The amounts of α-glucan and β-glucan were estimated by measuring released glucose using the phenol/sulfuric acid method [28].…”

Glucosylation of cell wall proteins in regenerating spheroplasts of Candida albicans

“…The mechanism by which these mannoproteins are incorporated into the cell wall is of considerable interest, because it might be exploited as a target for new antifungal agents. Non-covalently linked wall proteins are extractable with hot SDS [1,2]. The remaining mannoproteins are extractable with /?-1,3-glucanase, suggesting a covalent association with the fl-1,3-glucan frame-work of the cell wall [1,2,.…”

“…Non-covalently linked wall proteins are extractable with hot SDS [1,2]. The remaining mannoproteins are extractable with /?-1,3-glucanase, suggesting a covalent association with the fl-1,3-glucan frame-work of the cell wall [1,2,. These wall proteins were recently shown to contain a phosphodiester-linked side-chain of P-1,6-linked glucose residues by which the proteins are attached to the &1,3-glucan cell wall matrix [4-lo].…”

Characterization of a Schizosaccharomyces pombe morphological mutant altered in the galactomannan content

“…On the other hand, a great deal is known about the structure and biosynthesis [7] of the carbohydrate portion of the yeast mannoproteins, mainly in Saccharomyces cerevisiae, but much less data are available about the role of these molecules in cell wall structure. Mannoproteins may be important for cell wall porosity or morphogenesis [8,9]. The possibility that mannan may be cova-264 lently bound to the /3-glucan has been proposed but not yet proven [10,11].…”