Resistance of selected saprobic and zoopathogenic fungi to cycloheximide.

Spore germination was used as an assay to measure the sensitivities of selected fungi (Achlya bisexualis, Cladosporium sp., Trichophyton mentagrophytes and Microsporum gypseum) to cyclohexamide and to determine their abilities to adapt to the drug. Two patterns of response were noted. The saprobes, A. bisexualis and Cladosporium sp., demonstrated acquired resistance. Spores from hyphae previously exposed to cycloheximide either germinated in the presence of concentrations of the drug that completely inhibited spores from unexposed hyphae (Achlya), or germinates with a shorter lag and to a greater extent in the presence of the antibiotic than did spores from unexposed hyphae (Cladosporium). Hyphae of Achlya adapted at concentrations of cycloheximide in which spores did not germinate and hyphae of Cladosporium adapted more rapidly than spores. Achlya adapted to only 12 muM-cycloheximide whereas Cladosporium acquired resistance to 18 mM-cycloheximide. These fungi lost this acquired resistance after a single transfer to media lacking cycloheximide. The zoopathogens, T. mentagrophytes and M. gypseum, had a contrasting response, indicating constitutive resistance. Conidia from unexposed hyphae showed 90 to 100% germination on media containing up to 18 mM-cycloheximide; prior exposure to the drug did not affect their response.

[1]  I. Salkin Adaptation to cycloheximide: in vitro studies with filamentous fungi. , 1975, Canadian journal of microbiology.

[2]  W. Timberlake,et al.  Regulation of Macromolecular Synthesis, Colony Development, and Specific Growth Rate of Achlya bisexualis during Balanced Growth , 1974 .

[3]  T. Leighton,et al.  Physiological and biochemical changes associated with macroconidial germination in Microsporum gypseum. , 1972, Applied microbiology.

[4]  I. Salkin,et al.  Quantitative Evaluation of the Antifungal Properties of Cycloheximide , 1972, Antimicrobial Agents and Chemotherapy.

[5]  P. H. Tsao Selective Media for Isolation of Pathogenic Fungi , 1970 .

[6]  D. Griffin,et al.  Ribonucleic Acid Synthesis During the Differentiation of Sporangia in the Water Mold Achlya , 1969, Journal of bacteriology.

[7]  T. Leighton,et al.  Heat-induced macroconidia germination in Microsporum gypseum. , 1969, Applied microbiology.

[8]  H. Blank,et al.  Isolation and recognition of dermatophytes on a new medium (DTM). , 1969, Archives of dermatology.

[9]  G. Enderlein,et al.  Miller, I., and J. E. Freund: Probability and Statistics for Engineers. Prentice‐Hall, Englewood Cliffs, New Jersey 1965. 432 S., Preis 96. s. , 1968 .

[10]  K. Gundersen,et al.  Morphological changes and resistance induced in Saccharomyces pastorianus by the antibiotic cycloheximide. , 1962, Journal of general microbiology.

[11]  L. Ajello,et al.  A selective medium for the isolation of Coccidioides immitis. , 1951, Science.

[12]  A. J. Whiffen The Activity in Vitro of Cycloheximide (Acti-Dione) Against Fungi Pathogenic to Plants , 1950 .

[13]  A. J. Whiffen The Production, Assay, and Antibiotic Activity of Actidione, an Antiobiotic from Streptomyces griseus , 1948, Journal of bacteriology.

[14]  B. Leach,et al.  Actidione, an antibiotic from Streptomyces griseus. , 1948, Journal of the American Chemical Society.

[15]  A. J. Whiffen The production, assay, and antibiotic activity of actidione, an antibiotic from Streptomyces griseus. , 1948, Journal of bacteriology.