Susceptibility of species within the Sporothrix schenckii complex to a panel of killer yeasts

Abstract

The Sporothrix schenckii complex is the etiologic agent of sporotrichosis, a subacute or chronic mycosis which can affect humans and animals. Killer yeasts have been used in the medical field for development of novel antimycotics and biotyping of pathogenic fungi. The action of 18 killer yeasts on the growth of 88 characterized S. schenckii, Sporothrix globosa, Sporothrix brasiliensis, and Sporothrix mexicana clinical and environmental isolates was evaluated. Killer studies were performed on Petri dishes containing cheese black starch agar. The yeasts Candida catenulata (QU26, QU31, QU127, LV102); Trichosporon faecale (QU100); Trichosporon japonicum (QU139); Kluyveromyces lactis (QU30, QU99, QU73); Kazachstania unispora (QU49), Trichosporon insectorum (QU89), and Kluyveromyces marxianus (QU103) showed activity against all strains of the S. schenckii complex tested. Observation by optical microscopy of S. brasiliensis 61 within the inhibition haloes around the colonies of the killer yeasts QU100, QU139, and LV102 showed that there was no conidiation, but there was hyphal proliferation. The toxins were fungistatic against S. brasiliensis 61. There was no difference in susceptibility to the toxins among the S. schenckii species complex. Further investigations are necessary to clearly establish the mechanism of action of the toxins.

The ecology of killer yeasts: Interference competition in natural habitats

“…In laboratory cocultures under conditions permissive for toxin activity, killer strains are either considerably fitter than sensitive strains or they completely exclude sensitive strains (Bussey, Vernet, & Sdicu, 1988;McBride et al, 2008;Pieczynska et al, 2016;Wloch-Salamon, 2014). Killer yeasts can also inhibit or exclude filamentous fungi or bacteria under laboratory conditions (Morace et al, 1989;Perez et al, 2016;Polonelli & Morace, 1986;Stopiglia et al, 2014). Although killer toxins are effective at sensitive strain inhibition under laboratory conditions, ecologists do not fully understand the conditions under which they are effective in natural environments.…”

Caracterização microbiológica de extrato de frango líquido com sal nas etapas de processamento

“…It has lethal activity against other types of fungi (antifungal activity), due to the production of toxins. It caused significant inhibition in the fungus Sporothrix schenckii, which causes mycoses in animals and humans (STOPIGLIA et al, 2014). It can be used to control the contamination of fungi in food and plants (STOPIGLIA et al, 2014).…”

“…It caused significant inhibition in the fungus Sporothrix schenckii, which causes mycoses in animals and humans (STOPIGLIA et al, 2014). It can be used to control the contamination of fungi in food and plants (STOPIGLIA et al, 2014). The temperature does not develop at 45°C (FUENTEFRIA et al, 2008).…”