Abstract
Treatment of cells and purified cell walls of the fission yeast Schizosaccharomyces pombe with primuline reveals the septum as a bright fluorescent band. When polysaccharides containing (1 → 3)-β-, (1 → 6)-β- or (1 → 3)-α-glucosidic linkages are treated with primuline, only those molecules containing chains of (1 → 3)-β-glucosyl residues are stained. This implies that (1 → 3)-β-glucan is present in the septum of Schiz. pombe as the main constituent.