Introduction to Fungi, Third Edition

GALACTOMYCES (DIPODASCACEAE)
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of the initially predominant, fluconazolesensitive
C. albicans flora by fluconazoleresistant
C. dubliniensis strains especially in
those patients where C. albicans had failed to
develop resistance. Resistance may arise spontaneously
after prolonged treatment, and the
spread of resistant clones in hospitals may not
be as important with Candida as, for example,
with multiple drug-resistant bacteria (Taylor
et al., 2003).
processes of proteins of pharmacological interest
(Daly & Hearn, 2005).
10.5 Galactomyces (Dipodascaceae)
The genus Galactomyces (formerly called Endomyces)
is characterized by true hyphae which
10.4 Pichia (Saccharomycetaceae)
The genus Pichia contains 94 species (Kurtzman,
1998; Kirk et al., 2001) and is characterized by
budding cells, with only a few species also
producing arthroconidia, pseudohyphae and
hyphae. Sexual reproduction is by ascospores
(1 4 per ascus) which are often hat-shaped
(galeate). Molecular characterization of the
genus is still in progress (Suzuki & Nakase, 1999)
and will undoubtedly lead to rearrangements
in future.
Pichia is cosmopolitan and ubiquitous. A
surprising number of species has been isolated
from the frass of wood-attacking beetles
(Kurtzman, 1998); others grow on the exudates
(slime fluxes) of trees or on decaying cacti, or
they occur as contaminants of industrial fermentations.
Two species are of particular biotechnological
interest: Pichia jadinii (anamorph Candida
utilis), formerly called Torula yeast, has been
developed since World War I as a food yeast
for single-cell protein. It can utilize the pentoses
of pulping-waste liquors from the paper industry
and is also grown on other biological wastes
(Boze et al., 1995).
Pichia pastoris is interesting for a different
reason; it can utilize methanol by expressing
and secreting large quantities of alcohol oxidase.
Since the protein glycosylation chains of
P. pastoris are similar to those of humans, and
because the products of heterologous genes are
secreted efficiently, P. pastoris has advantages
over S. cerevisiae in the industrial production
Fig10.10 Galactomyces candidus. (a) Vegetative hyphal apex.
The two lateral branches near the base are developing
conidiophores. (b) Conidiophore showing the development
and separation of arthroconidia. (c) Gametangia developing as
lateral bulges of the hyphae on either side of a septum.
(d) Fusion of gametangia to form asci. In one ascus, a single
ascospore is differentiated. (e) Mature asci, each containing
a single ascospore.