In the previous papers we reported that the antibiotic Polyoxin D induced the characteristic swelling of the mycelia of fungi, ^{1, 2)} and strongly inhibited the incorporation of ¹⁴C-glucosamine into the fungal cell wall chitin.³⁾ The present work has been conducted to further investigate the influence of this antibiotic on the fungal cell wall biosynthesis.
Polyoxin D did not inhibit the incorporation of ¹⁴C-glucose, ¹⁴C-amino acids and ¹⁴C-sodium acetate into the cell wall. In addition, UDP-N-acetylglucosamine, a precurcor of chitin biosynthesis of cell wall, was accumulated in the Polyoxin D-treated mycelia of Cochliobolus miyabeanus more than 150 to 160% of that accumulated in the untreated one.
Chitin synthetase prepared from Piricularia oryzae which is not treated with Polyoxin D was completely inhibited by the addition of 0.1ppm of Polyoxin D. The fungitoxicity of Polyoxins A to G was positively related to their inhibition of ¹⁴C-glucosamine incorporation into the cell wall chitin of C. miyabeanus. From above results, it became evident that the antibiotic Polyoxin complex inhibited the biosynthesis of fungal cell wall chitin.

This article cannot obtain the latest cited-by information.