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Candida albicans is a dimorphic fungus, i.e. it can take two forms. Most of the time it exists as oval, single yeast cells, which reproduce by budding. Most yeasts do not produce mycelia (a mass of branching, threadlike hyphal filaments), but Candida has a trick up its sleeve. Normal room temperatures favour the yeast form of the organism, but under physiological conditions (body temperature, pH, and the presence of serum) it may develop into a hyphal form. Pseudohyphae, composed of chains of cells, are also common. In the video, you can see yeast cells and a few elongated cells which have begun to grow into a hypha:
There are many species of the genus Candida which cause the disease known as candidiasis or "thrush". Candida is a commensal organism found in 40-80% of normal humans, and is present in the mouth, gut, and vagina. Problems start when a person experiences some alteration in:
Although
Candida most frequently infects the skin and mucosal surfaces, it can
cause systemic infections manifesting as pneumonia, septicaemia or endocarditis
in severely immunocompromised patients. There does not appear to be significant
difference in pathogenic potential of different Candida strains, therefore
establishment of infection appears to be determined by host factors and not the
organism itself. However, the ability to assume various forms may be related
to the pathogenicity of the organism. The yeast form is 10-12 µm in diameter.
Pseudohyphae (chains of cells) may be formed from budding yeast cells which remain
attached to each other. Chlamydospores may be formed on the
pseudomycelium. Fortunately, several drugs are available to treat serious systemic
infections, e.g. itraconazole and fluconazole.
Fungal
Biology: Understanding the Fungal Lifestyle
by D.H. Jennings, G.Lysek.
A concise introduction to the fundamental properties and activities of fungi
in their natural environment. This approach avoids the repetition of taxonomy
and life cycle studies found in similar texts. The environmental perspective
used to illustrate the book helps readers develop their understanding of basic
principles.
(Amazon.co.UK)
Introduction
to Modern Mycology
by J.W. Deacon.
Provides students of microbiology, mycology and biology with an introduction
to fungi. Emphasizes the behaviour, physiology, activities and practical significance
of fungi, and includes extensive sections on fungal pathogens of plants, animals
and humans, the roles of fungi in major environmental processes, the use of fungi
as biological control agents of pests and pathogens, fungal cell biology, and
the application of fungal molecular genetics. Contains numerous photographs,
line drawings, and diagrams.
(Amazon.co.UK)