Studies of the cell walls of Schizophyllum commune

Mechanically isolated cell wall materials of eight strains of Schizophyllum commune were studied by chemical and enzymatic procedures. Isolated wall material of each strain was separated by chemical methods into three fractions: A (cold alkali-soluble, , amorphous), B (warm alkali-soluble, amorphous), and C (alkali-insoluble, retaining appearance of hyphal fragments). Chemical tests indicated the presence of chitin in Fraction C and the absence of cellulose, lignin and pectic substances from all fractions. Analyses of acid hydrolysates indicated the presence of glucose in Fractions A, B and C, of hexosamine in Fraction C and the absence of galactose, mannose, 6-deoxyhexoses, xylose and other pentoses from all fractions. Unfractionated material, Fraction A and Fraction B were slightly attacked by commercial cellulase whereas Fraction C was heavily attacked. Commercial chitinase by itself did not attack Fraction C or unfractionated material to a significant extent. In the presence of cellulase, it was active upon Fraction C. Qualitative differences in cell wall composition between strains were not detected; however, quantitative differences were observed in the proportion of Fraction A and Fraction C as well as in the amount of the various breakdown products in certain strains. It is visualized that the cell wall of this fungus consists of a core of chitin covered by or intermeshed with glucose-containing polymers.