Production of Bacteriolytic Enzymes and Degradation of Bacterial Cell Walls During Growth of Agaricus bisporus on Bacillus subtilis

Abstract

Summary: The mechanism by which the mycelium of Agaricus bisporus can use Bacillus subtilis as sole carbon and nitrogen source was investigated. During fungal growth more than 80% of the muramic acid and diaminopimelic acid residues in the bacterial walls disappeared from the microbial biomass and appeared as soluble glycopeptides. Culture supernatants dissolved purified walls of B. subtilis, and bacteriolytic enzymes were obtained by ion-exchange chromatography of these supernatants. The main bacteriolytic enzyme activity was found to be a β-N-acetylmuramidase. Soluble bacterial wall fragments were partially purified by chromatography of the culture fluids. The chemical properties of these fragments were consistent with their having been produced by β-N-acetylmuramidase action on the peptidoglycan of the B. subtilis cell wall.