Saccharomyces cerevisiae mutant displaying beta-glucans on cell surface.
The deletion of MCD4 leads to an increase in beta-1,6-glucan level and a decrease in glycosylphosphatidylinositol-anchored protein and mannan levels in the cell wall of Saccharomyces cerevisiae, suggesting that mcd4 deletion mutant (mcd4Delta) displays beta-glucans on the cell surface without a mannan cover. An observation of the cell surface of mcd4Delta cells and an examination of the effect of contact between mcd4Delta cells and mouse macrophages indicated that macrophages were activated by contact with mcd4Delta cells displaying beta-glucans on the cell surface. We further examined the effect of intraperitoneal ethanol-fixed mcd4Delta cells on the survival period of mice infected with Candida albicans. mcd4Delta cells prolonged the survival period, implying that mcd4Delta cells may enhance the immune function of mice via macrophage activation. Moreover, we examined the structures of beta-glucans (i.e., alkali- and acetic acid-insoluble beta-glucans) extracted from mcd4Delta with (13)C-NMR and the effect of extracted beta-glucans on TNF-alpha secretion from macrophages. The structures of the beta-glucans from mcd4Delta differed from those of wild type (WT); however, there was no difference in tumor necrosis factor-alpha (TNF-alpha) secretion level between beta-glucans from mcd4Delta and those from WT. The yield of purified beta-glucans obtained from dry cells of mcd4Delta was higher than that obtained from dry cells of WT. mcd4Delta may be a superior strain for the preparation of beta-glucans.
Sakai
Yumiko
Y
Department of Applied Chemistry and Bioengineering, Graduate School of Engineering, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan.
Azuma
Masayuki
M
Takada
Yuki
Y
Umeyama
Takashi
T
Kaneko
Aki
A
Fujita
Tsuyoshi
T
Igarashi
Koichi
K
Ooshima
Hiroshi
H
D000818:Animals; D002176:Candida albicans / Q000276:immunology; D002462:Cell Membrane / Q000737:chemistry; D000431:Ethanol / Q000737:chemistry; D017353:Gene Deletion; D017261:Glycosylphosphatidylinositols / Q000032:analysis / Q000378:metabolism; D008262:Macrophage Activation; D008264:Macrophages / Q000187:drug effects / Q000276:immunology; D008565:Membrane Proteins / Q000235:genetics*; D051379:Mice; D008855:Microscopy, Electron, Scanning; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics*; D047071:beta-Glucans / Q000032:analysis / Q000302:isolation & purification* / Q000378:metabolism* / Q000494:pharmacology
D017261:Glycosylphosphatidylinositols; C118052:MCD4 protein, S cerevisiae; D008565:Membrane Proteins; D029701:Saccharomyces cerevisiae Proteins; D047071:beta-Glucans; C064197:beta-1,6-glucan; D000431:Ethanol