MORPHOLOGICAL CHANGES INDUCED IN FUNGI BY ANTIBIOTICS

In tests of 31 antibiotics, 29 inhibited growth of Botrytis cinerea and of these, 18 induced morphological changes. Terminal and lateral branching of the hyphae was induced by actinomycin D, aspergillic acid, citrinin, cyanein, cycloheximide, desertomycin and polyene antibiotics. Curling of the hyphae was induced by griseofulvin and narrowing of the hyphae by citrinin. Some antibiotics at different concentrations produced several types of morphological changes. For example, aspergillic acid, desertomycin and flavofungin also induced terminal bulging of the hyphae. Growth of the dimorphic fungus Paecilomyces viridis was inhibited by 24 antibioties, nine of which induced morphological changes. Branching of the hyphae was induced by azalomycin F, citrinin, eyanein, desertomycin, patulin, rugulosin and trichothecin. Griseofulvin had a curling effect. Except for rugulosin, the above antibiotics, in higher concentrations, induced yeast-like growth of Paecilomyces viridis. Morphological changes were also induced by inhibitors of RNA and protein synthesis and by antibiotics injuring the cell membranes. Antibiotics with different mechanisms of action induced similar morphological changes. © 1969 Institute of Microbiology, Academy of Sciences of the Czech Republic.