ABSTRACT
Antibiotic production by dermatophyte fungi has been demonstrated in vivo in the lesions of patients with dermatomycoses. Patients infected with antibiotic-producing strains more frequently carried cocci resistant to penicillin and other antibiotics than did patients infected with non-producer strains. The total bacterial load was less in lesions caused by producer fungi. In vitro studies demonstrated the selection of penicillin-resistant S. aureus from mixed populations of resistant and sensitive cells.
Subject(s)
Anti-Bacterial Agents/biosynthesis , Bacteria/growth & development , Dermatomycoses/microbiology , Epidermophyton/metabolism , Skin/microbiology , Trichophyton/metabolism , Female , Humans , Male , Penicillin Resistance , Staphylococcus aureus/drug effects , Staphylococcus aureus/growth & developmentABSTRACT
Thirty-two clinical isolates of anthropophlic dermatophytes were examined for their capacity to produce antibiotics in liquid culture and on human stratum corneum in vitro. Antibiotics were detected and classified using agar diffusion bioassays and chromatographic analysis. Twenty-four isolates produced antibiotic substances in liquid culture filtrates; some strains produced more than one antibiotic. Only four isolates produced detectable levels of antibiotics when grown on stratum corneum unless an artificial sweat mixture was used as a nutrient supplement, when the number rose 11. Respresentatives of all species studied produced benzyl penicillin-like substances. Some Trichophyton isolates also produced streptomycin-like antibiotics, a characteristic previously unrecorded for eukaryotic organisms. Other antibiotics, which apart from azalomycin F could not be properly classified, were produced by Epidermophyton floccosum. Antibiotic production occurred over the normal skin temperature range but sometimes the type of antibiotic produced and the frequency of detection appeared to be influenced by the incubation temperature.