Ulocladium
Characteristics: Type I allergen. Rare pathogen. Not known to be toxigenic.
Description: It is often found in soil, dung, paint, grasses, fibers, wook, decaying plant material, paper, and textiles with a dark or rusty brown coloration with a granular or velvety texture. It is disseminated as a dry spore by the wind. Indoors, growth this fungus is commonly found on gypsum board, paper, pain, tapestries, jute, and straw materials. As an allergen, it has been known to cause Type I allergen symptoms including hay fever and asthma. As an allergen, it also cross reacts with Alternaria. As a pathogen it has been known to cause rare subcutaneous tissue infection. It is not known to be a toxigenic agent.
Ustilago
Characteristics: There are no reports of human infection. No information is available regarding toxicity. Smuts have been documented as a cause of Type I allergies.
Description: Ustilago is a genus in the smut fungi, which are the Ustilaginales. The smuts are major plant pathogens. There are no reports of human infection. No information is available regarding toxicity. Smuts have been documented as a cause of Type I allergies (hay fever, asthma). Ustilago is present in the air as dry brown spores (teliospores) and will grow in culture as a yeast (basidiospores). Natural habitat includes grasses, cereal crops, weeds, other fungi, and other flowering plants (many types).
Verticillium
Characteristics: Allergenicity has not been well studied. Rare pathogen. Not considered toxigenic.
Description: Verticillium species are common and are most closely related to Acremonium, and Tritirachium. Former names include Acrostalagmus and Diheterospora. Verticillium is a major plant pathogen and is also parasitic on other fungi and insects. It is normally considered to be nonpathogenic in humans. A few cases of keratitis have been reported but remain questionable. Allergenicity has not been well studied. Verticillium produces an antifungal compound vergosin and an antitumor antibiotic, as well as a wide variety of additional compounds used by various industries. Very little other information is available regarding inhalation health effects or toxicity to humans. May be identified on surfaces by tape lifts, tease mounts from bulk samples, and in air by culturable (Andersen) samples. (Spores do not have distinctive morphology and would be categorized as “other colorless” on spore trap samples.) Widespread in decaying vegetation and in the soil.
Wallemia
Characteristics: Type I allergen. Rare pathogen. Produces toxins.
Description: It is often found in soil, hay, and textiles with a light brown or tan coloration. It is disseminated as a dry spore by the wind. Indoors, growth this fungus is commonly found on relatively dry surfaces such as wood in crawl spaces. As an allergen, it has been known to cause Type I allergen symptoms including hay fever and ashtma. As a pathogen it has rarely been known to cause human abscesses. As a toxigenic agent, it produces walleminol, tryptophol, and UCA 1064-beta. Wallemia is a keratinophilic, osmophilic fungus (grows on highly concentrated solutions e.g. salt and sugar).
Yeasts
Fungi may be unicellular or multicellular. Yeasts are unicellular fungi that reproduce primarily by budding and in culture, form pasty colonies similar to those of bacteria.
Zygomycetes
Characteristics: Zygomycetes are one of the four major groups of fungi, the others being the Oomycetes, the Ascomycetes,
Description: Zygomycetes are one of the four major groups of fungi, the others being the Oomycetes, the Ascomycetes, and the Basidiomycetes. Zygomycetes are common, fast growing, and often overgrow and/or inhibit other fungi nearby. Rhizopus and Mucor are two of the most common Zygomycetes seen in the indoor environment. However, others are seen as well, including Syncephalastrum, Circinella, Mortierella, Mycotypha, Cunninghamella, and Choanephora. For further information, please see descriptions of these individual genera.
Zygosporium
Characteristics: No information is available regarding health effects or toxicity. Allergenicity has not been studied.
Description: Zygosporium species comprise a small proportion of the fungal biota. No information is available regarding health effects or toxicity. Indoor growth usually found on damp walls. Natural habitat is primarily dead leaves (many plants), with occasional isolations from soil.
