[Chemical and enzymatic degradation of Helminthosporium spiciferum cell walls. Protective role of pigments].

Cell walls of the fungus Helminthosporium spiciferum, prepared by mechanical grinding of the cells, were treated chemically and with helicase. The purified cell walls and the fractions were analyzed chemically and micromorphologically to localize the major cell-wall constituents and to determine the protective role of the pigments against degradative processes. The encrusting of the external area by the pigments associated with chitin formation leads to an increased resistance of this cell-wall area against the degradative processes.