impaginato piccolo - Società Italiana di Parassitologia (SoIPa)

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Table 1. Current composition of the genus Malassezia.
which included DNA/DNA relatedness and comparison
of 26S rRNA sequences from a large number of isolates,
confirmed the presence of phenotypical variants
and clearly indicated the need to create new Malassezia
species (Guillot and Guého 1995). Consequently, lipiddependent
species M. globosa, M. slooffiae, M. restricta
and M. obtusa were described by Guého et al. in
1996.
More recently, the number of lipid-dependent
Malassezia species increased. New species were isolated
from human skin: M. dermatis (Sugita et al., 2002),
M. japonica (Sugita et al., 2003) and M. yamatoensis
(Sugita et al., 2004). Others were isolated from animals:
M. nana (from cat and cattle) (Hirai et al.,
2004), M. caprae (mainly from goats) and M. equina
(mainly from horses) (Cabanes et al. 2007). To date,
J. Guillot et al. - History of the genus Malassezia
Species Description Isolated from humans Isolated from animals
M. furfur Baillon, 1889 • Healthy skin
• Cutaneous lesions (mainly
pityriasis versicolor)
• Systemic infections
the genus Malassezia is composed of one non lipiddependent
species (M. pachydermatis) and 12 lipiddependent
species (Table 1). No doubt that additional
new species will be described in close future.
New concepts
• Healthy skin
M. pachydermatis (Weidman) Dodge, 1925 • Systemic infections • Healthy skin (dogs, cats, many
other animals)
• Cutaneous lesions (mainly otitis
and seborrheic dermatitis in
dogs)
M. sympodialis Simmons & Guého, 1990 • Healthy skin
• Cutaneous lesions (mainly
atopic dermatitis)
M. globosa Midgley, Guého & Guillot, 1996 • Healthy skin
• Cutaneous lesions (mainly
seborrheic dermatitis or pityriasis
versicolor)
M. obtusa Midgley, Guillot & Guého, 1996 • Healthy skin
• Cutaneous lesions
M. restricta Guého, Guillot & Midgley, 1996 • Healthy skin
• Cutaneous lesions (mainly
seborrheic dermatitis)
M. slooffiae Guillot, Midgley & Guého, 1996 • Healthy skin
• Cutaneous lesions
M. dermatis Sugita et al., 2002 • Healthy skin
• Cutaneous lesions
• Healthy skin
• Cutaneous lesions (otitis in cats)
• Healthy skin
• Cutaneous lesions (otitis in cats)
• Healthy skin (in pigs)
• Cutaneous lesions (otitis)
M. nana Hirai et al., 2004 • Cutaneous lesions (otitis in cat
and cattle)
M. japonica Sugita et al., 2003 • Healthy skin
• Cutaneous lesions
M. yamatoensis Sugita et al., 2004 • Healthy skin
• Cutaneous lesions
M. caprae Cabanes et al., 2007 • Healthy skin (mainly in goats)
M. equina Cabanes et al., 2007 • Healthy skin (mainly in horses)
• Cutaneous lesions (in horses)
In a recent paper, Xu et al. (2007) described the
genome and secretory proteome of two Malassezia
species (M. globosa and M. restricta). They suggested
that the lipid dependence of these species can be
explained by the apparent absence of a fatty acid synthase
gene. In parallel, the presence of multiple secreted
lipases to aid in harvesting host lipids was demonstrated.
The genome of M. globosa revealed the presence of mating-type
genes, providing an indication that Malassezia