Candida colliculosa

Teleomorph: Torulaspora delbrueckii

Culture: Colonies (SDA) white to cream-coloured smooth, glabrous yeast-like.

Microscopy: Spherical to ellipsoidal budding blastoconidia, 2-6 x 3-7 µm in size. Ascospores may be produced on 5% malt extract or cornmeal agar after 5-30 days at 25C.

India Ink Preparation: Negative - No capsules present.

Dalmau Plate Culture on Cornmeal and Tween 80 Agar: Budding yeast cells only. No pseudohyphae or true hyphae produced.

Physiological Tests:

Germ Tube test is Negative
Hydrolysis of Urea is Negative
Growth on Cycloheximide medium is Negative
Growth at 37C is Variable

Fermentation Reactions: Where fermentation means the production of gas and is independent of pH changes.

Positive: Glucose.
Variable: Sucrose; Galactose; Maltose; Trehalose
Negative: Lactose.

Assimilation Tests:

Positive: Glucose; D-Mannitol; 2-K-D-gluconate.
Variable: Galactose; L-Sorbose; Maltose; Raffinose; Melezitose; Trehalose; Raffinose; Melezitose; D-Xylose; Glycerol; Ribitol; D-Glucitol;  α-M-D-glucoside; D-Gluconate; DL-Lactate; D-Glucuronate
Negative: D-Arabinose; L-Arabinose; D-Ribose; Cellobiose; L-Rhamnose; D-Glucosamine; myo-Inositol; Lactose; N-A-D-glucosamine; Melibiose; Erythritol; Nitrate; Soluble Starch; Galactitol.

MIC data is limited.  Antifungal susceptibility testing of individual strains is recommended.

Key Features: asci containing 1-4 spheroidal ascospores, variable growth at 37C and a variable sugar assimilation profile. C. colliculosa is a rare cause of candidemia. RG-1 organism.

Clinical significance:

Candida viswanathii is only rarely isolated from clinical specimens.

Mycosis: Candidiasis

Further reading:

Kreger-Van Rij, N.J.W. (ed) 1984. The Yeasts: a taxonomic study. 3rd Edition. Elsevier Science Publishers B.V., Amsterdam, The Netherlands.

Rippon, J.W. 1988. Medical Mycology. 3rd Edition. W.B. Saunders Co., Philadelphia, USA.