Electron Microscopic Localization of Polysaccharides in Fungal Cell Walls

Abstract

The fungal cell wall is a specialized structure involved in both the maintenance of cell shape and protection against unfavourable environmental conditions (Rosenberger, 1976; Wessels and Sietsma, 1979), The specific properties of fungal cell walls such as their morphological features, mechanical strength, and resistance to antifungal compounds are intimately related to their particular chemical composition (Aronson, 1981; Farkas, 1979). With the advent of new methods of analysis, the complexity and diversity in fungal wall structure has become evident (Benhamou, 1988, 1989b; Benhamou et al., 1990a; Harder et al.,1986). Although there are still gaps in our knowledge of the chemical composition and three-dimensional organization of fungal cell walls, the availability of modern techniques, especially that of gold cytochemistry, has made possible the development of complementary approaches for a more accurate investigation of fungal cell walls at the molecular level (Benhamou and Ouellette, 1986b, 1987; Benhamou et al.,1987; Berg et al.,1988; Bonfante-Fasolo et al.,1986; Chong et al., 1985). The rationale for such investigations was that they could pot only improve our knowledge of the wall structure, but also contribute to a better understanding of the functional specialization of cell wall components by visualizing their precise location within the wall matrix (Erdos, 1986).