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Trichosporon asteroides (Rischin) Ota

Colony characteristics. Colonies (SGA) restricted, dry, cream-coloured, cerebriform, with a radially furrowed outer zone. The meristematic form is punctiform and brownish.

Microscopy. Budding cells and lateral conidia absent. Arthroconidia elongate; hyphae often present. Appressoria absent. The meristematic form consists of hyphae which swell, become multiseptate and fall apart into smaller cell packets.

Physiology.

Fermentation: Growth: Glucose Galactose l-Sorbose Sucrose Maltose Cellobiose ","-Trehalose Lactose Melibiose Raffinose Melezitose Inulin Soluble starch d-Xylose

–   + + v + + + + + – – + – + +

1-Arabinose d-Arabinose d-Ribose l-Rhamnose d-Glucosamine (C) n-Acetyl-d-glucosamine Methanol Ethanol Glycerol meso-Erythritol Ribitol Galactitol d-Mannitol d-Glucitol "-Methyl-d-glucoside Salicin d-Gluconate

+ + + + v + – + + + v – v v + v +

dl-Lactate Succinate Citrate myo-Inositol Nitrate Vitamin-free 2-Keto-d-gluconate 5-Keto-d-gluconate d-Glucuronate 10% NaC1/5% glucose 0.01% Cycloheximide 0.1% Cycloheximide Urease Starch formation Growth at 37oC Growth at 42oC

+ + + + – – + + + + v v + w v –

Differential diagnosis. The species assimilates l-arabinose but not myo-inositol. It cannot reliably be distinguished physiologically from T. asahii.

Molecular diagnostics. LSU restriction map based on NCBI AF075513:

Pathogenicity. BSL-2. Very rare agent of superficial infections (Rischin, 1921).

References. Guého et al. (1992b, 1994).

Antifungal susceptibility