Polysaccharidase Production and Cell Wall Degradation by Several Salt Marsh Fungi

Three salt marsh fungi (Pleospora pelagica, Pleospora vagans, Phaeosphaeria typharum) were examined for their ability to produce cell wall polysaccharidases when cultured in a medium containing cell walls isolated from Spartina alterniflora as the sole carbon source. Enzymatic activities detected in culture filtrates after six da of growth were α-L-arabinosidase, α-D-galactosidase, β-D-galactosidase, β-D-glucosidase, β-D-xylosidase, arabanase, cellulase, pectinase, and xylanase. Not all fungi produced the same enzymes. Enzymatically active culture filtrates from these fungi, as well as from the salt marsh fungus Buergenerula spartinae, were also able to solubilize isolated cell walls as measured by reducing sugar liberation. The merits of using isolated cell walls as enzyme substrates are discussed.