Yeast Cell Wall and Cell Surface

Abstract

The structure and organization of the yeast cell wall and the nature of the cell surface have been investigated in terms of the composition of the wall; the structures of the wall components; the immunochemistry of the cell surface and binding of dyes, lectins, or specific antibodies; the degradative action of enzymes; and the visual evidence from scanning and thin-section electron microscopy. Most or all of these methods have been applied to the cells during vegetative growth, sporulation, and mating, and the analyses have been furthered by the availability in recent years of a variety of cell-wall mutants. A general conclusion from all of these studies is that yeast cell walls show less apparent organization than bacterial walls but that the yeast wall is as metabolically active and the cell surface as antigenically polymorphic as those of Gram-positive bacteria. To keep this review manageable, it will be limited in most instances to Saccharomyces cerevisiae, with only occasional reference to other yeasts. The aim is to treat the subject topics briefly and to direct the reader to several recent reviews in which leading references to the original literature can be found.

VEGETATIVE CELL WALL
Composition and Structure
Three components, glucan, mannoprotein (previously called mannan), and chitin, make up over 90% of the cell wall, whereas only small and variable amounts of lipid have been reported (Phaff 1971). When grown on hexadecane, however, the cell wall of Candida tropicalis increases in covalently linked fatty acid (Kappeli et al. 1978). Thus, cell-wall composition...