DESCRIPTIONS OF MEDICAL FUNGI

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Descriptions of Medical Fungi
Candida parapsilosis complex
Lodderomyces elongisporus (Recca & Mrak) van der Walt
Lodderomyces elongisporus has been isolated from soft drinks and juice concentrates,
natural fermentations of cocoa, soil, an infected fingernail, human blood infections and
from baby cream. Initially isolates appeared to be atypical forms of C. parapsilosis,
but sequence analysis identified them as L. elongisporus. In view of these findings,
L. elongisporus may be more common among clinical isolates than initially thought
(Lockhart et al. 2008a, Kurtzman).
RG-1 organism.
Culture: Colonies (SDA) white to cream-coloured smooth, glabrous, yeast-like.
Microscopy: Ellipsoid to elongate budding blastoconidia, 2.6-6.3 x 4-7.4 µm, with
occasional spherical forms present.
India Ink Preparation: Negative - no capsules present.
Dalmau Plate Culture: Abundant, much-branched pseudohyphae produced.
Ascospore Formation: Asci are unconjugated, persistent, and are transformed from
budding cells. Each ascus forms one, rarely two, long-ellipsoid ascospores. Ascospores
observed on V8 agar after 7-10 days at 25 O C.
Physiological Tests: + Positive, - Negative, v Variable, w Weak, s Slow
Germ Tube - L-Sorbose + L-Arabinose - D-Glucitol +
Fermentation Sucrose + D-Arabinose - α-M-D-glucoside +
Glucose + Maltose + D-Ribose - D-Gluconate +,w
Galactose - Cellobiose - L-Rhamnose - DL-Lactate -
Sucrose - Trehalose + D-Glucosamine - myo-Inositol -
Maltose - Lactose - N-A-D-glucosamine + 2-K-D-gluconate +
Lactose - Melibiose - Glycerol + D-Glucuronate -
Trehalose + Raffinose - Erythritol - Nitrate -
Assimilation Melezitose + Ribitol + Urease -
Glucose + Soluble Starch - Galactitol - 0.1% Cycloheximide -
Galactose + D-Xylose +,w D-Mannitol + Growth at 37 O C +
Key Features: In the absence of ascospores, L. elongisporus cannot be distinguished
physiologically from C. parapsilosis, C. orthopsilosis and C. metapsilosis but can be
identified based on ITS sequencing (Asadzadeh et al. 2009, Borman et al. 2009,
Tavanti et al. 2005) and MALDI-TOF MS analysis.