Wickerhamomyces anomalus
Synonymy:
Candida pelliculosa
Wickerhamomyces anomalus has been reported from cases of candidaemia and catheter related infections in humans and has been isolated from soil, grains, fruit and warm-blooded animals.
RG-1 organism.
Culture:
Colonies (SDA) white to cream-coloured smooth, glabrous, yeast-like.
Microscopy:
Spherical to ellipsoidal budding blastoconidia, 2-4 x 2-6 µm. Pseudohyphae may be present. Asci when present, containing one to four hat-shaped ascospores.
India ink preparation:
Negative - no capsules present.
Dalmau plate culture:
Spherical to ellipsoidal budding yeast cells and abundant pseudohyphae in most strains.
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 | - | L-Arabinose | v | D-Glucitol | + |
| Fermentation | Sucrose | + | D-Arabinose | - | 𝝰-M-D-Glucoside | + | |
| Glucose | + | Maltose | + | D-Ribose | v | D-Gluconate | v |
| Galactose | v | Cellobiose | + | L-Rhamnose | - | DL-Lactate | + |
| Sucrose | + | Trehalose | + | D-Glucosamime | - | myo-Inositol | - |
| Maltose | v | Lactose | - | N-A-D-glucosamine | - | 2-K-D-Gluconate | - |
| Lactose | - | Melibiose | - | Glycerol | + | D-Glucuronate | nd |
| Trehalose | - | Raffinose | + | Erythritol | + | Nitrate | + |
| Assimilation | Melezitose | + | Ribitol | v | Urease | - | |
| Glucose | + | Soluble Starch | + | Galactitol | - | 0.1% Cycloheximide | - |
| Galactose | v | D-Xylose | v | D-Mannitol | + | Growth at 37C | v |
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 | 48 | 3 | 14 | 21 | 9 | 1 | |||||||
| FLU | 48 | 3 | 12 | 27 | 7 | ||||||||
| ISAV | 5 | 1 | 4 | ||||||||||
| VORI | 48 | 3 | 2 | 27 | 13 | 3 | |||||||
| POSA | 48 | 1 | 1 | 3 | 9 | 6 | 14 | 12 | 2 | ||||
| ITRA | 8 | 1 | 1 | 3 | 3 | ||||||||
| ANID | 22 | 21 | 1 | ||||||||||
| MICA | 22 | 20 | 2 | ||||||||||
| 5FC | 8 | 7 | 1 |
References
- Diekema, D.J., Messer, S.A., Boyken, L.B., et al. (2009) In vitro activity of seven systemically active antifungal agents against a large global collection of rare Candida species as determined by CLSI broth microdilution methods. Journal of Clinical Microbiology, 47, 3170-3177.
- Kurtzman, C.P. (2011) Chapter 80, Wickerhamomyces Kurtzman, Robnett & Basehoar-Powers (2008), in Kurtzman, C.P., Fell, J.W. and Boekhout, T. (eds), The Yeasts, a Taxonomic Study, 5th edition, pp. 899-917.