Debaryomyces hansenii
Synonymy:
Candida famata.
Debaryomyces hansenii is a common environmental isolate.
It may be isolated from human skin, and is only rarely recovered from blood stream infections.
RG-1 organism.
Culture:
Colonies (SDA) white to cream-coloured smooth, glabrous, yeast-like.
Microscopy:
Ovoid to broadly ellipsoidal budding blastoconidia, 3.5-5 x 2-3.5 µm in size. No pseudohyphae produced. Asci when present are spherical, persistent, containing one to two spherical ascospores with rough walls.
India ink preparation:
Negative - no capsules present.
Dalmau plate culture:
Spherical to ovoid budding yeast cells only. Pseudohyphae are usually lacking.
Molecular identification:
ITS sequencing recommended.
MALDI-TOF MS:
Able to accurately identify this species.
| Physiological Tests: + Positive, - Negative, v Variable, w Weak, s Slow, nd No Data | |||||||
|---|---|---|---|---|---|---|---|
| Germ Tube | - | L-Sorbose | v | L-Arabinose | +,w | D-Glucitol | +,w |
| Fermentation | Sucrose | + | D-Arabinose | v | 𝝰-M-D-Glucoside | +,w | |
| Glucose | -,w | Maltose | + | D-Ribose | v | D-Gluconate | +,w |
| Galactose | -,w | Cellobiose | + | L-Rhamnose | v | DL-Lactate | v |
| Sucrose | -,w | Trehalose | + | D-Glucosamime | v | myo-Inositol | - |
| Maltose | -,w | Lactose | v | N-A-D-glucosamine | v | 2-K-D-Gluconate | + |
| Lactose | - | Melibiose | v | Glycerol | + | D-Glucuronate | v |
| Trehalose | -,w | Raffinose | + | Erythritol | v | Nitrate | - |
| Assimilation | Melezitose | v | Ribitol | + | Urease | - | |
| Glucose | + | Soluble Starch | v | Galactitol | v | 0.1% Cycloheximide | v |
| Galactose | + | D-Xylose | + | D-Mannitol | + | Growth at 40C | - |
Key features:
Germ tube negative yeast and sugar assimilation pattern.
| Antifungal | No | ≤0.03 | 0.06 | 0.125 | 0.25 | 0.5 | 1 | 2 | 4 | 8 | 16 | 32 | ≥64 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| AMB | 29 | 2 | 3 | 7 | 14 | 2 | 1 | ||||||
| FLU | 78 | 9 | 18 | 14 | 9 | 9 | 11 | 2 | 3 | 3 | |||
| VORI | 81 | 48 | 16 | 9 | 4 | 2 | 1 | 1 | |||||
| POSA | 75 | 20 | 22 | 10 | 8 | 10 | 2 | 3 | |||||
| ITRA | 14 | 2 | 2 | 1 | 4 | 3 | 2 | ||||||
| ANID | 26 | 1 | 2 | 3 | 1 | 9 | 10 | ||||||
| MICA | 25 | 5 | 1 | 2 | 8 | 6 | 3 | ||||||
| 5FC | 14 | 1 | 7 | 1 | 1 | 2 | 2 |