Abstract:

Some Chaetomium spp. Are capable of antagonizing several plant pathogenic fungi through production of antibiotics and mycoparasitism. Secretion of lytic enzymes, mainly including glucanases and chitinases, is considered the most important step in the mycoparasitic process. In this study, an about 110kDa exo-β-1,3-glucanase from C. spirale ND35 was detected both in culture filtrate and directly on PAGE and IEF gels, as well as chitinases, although protease was not detectable on Litmus milk agar plates. Coiling and penetrating the hyphae of host fungus Valsa mali were observed by scanning electron microscope (SEM), which may be related to the synergistic interaction between β-1,3-glucanase and chitinases. Β-1,3-glucanase activity of C. spirale ND35 varied considerably when C. spirale ND35 was grown in different carbon sources during various incubation time, and might be subjected to both induction by substrate and catabolite repression.

Key words: Chaetomium spirale ND35, cell wall degrading enzymes, assays of enzyme activities, mycoparasitism, scanning electron microscope