Nature
Ulocladium chartarum is a common mold, renamed Alternaria chartarum following extensive genotyping (1). Molds of the genus Ulocladium are common saprobes and plant pathogens, able to cause disease in oaks (2). They can also be frequently found in soil (3), indoors (4, 5) and are considered an indicator of water damaged buildings (6). U. chartarum has been isolated from mural paintings, from plant residues within the plaster layer (7). Ulocladium spp., including U. chartarum, were also cultured from a number of water-damaged building materials, of which gypsum appeared to be the most susceptible (8). In a study focusing on environmental conditions of UK homes, 9% of 204 fungal isolates taken from visible mold tested positive for an antibody specific for Ulocladium/Alternaria/Epicoccum by enzyme-linked immunosorbent assay (ELISA) (9).
During in vitro culture, U. chartarum colonies appear dense, with tall hyphae extending from the main mycelium. The colonies are olive-black, with a cottony appearance and regular margins (7). The mold presents black conidia (a type of spore) and hyphae due to their melanin content, with a rough surface, usually in a short chain with septae that can be both longitudinal and transverse (6, 7). The spores of the genus Ulocladium are large and thought to settle more rapidly when airborne when compared to other types of spores (5). Highest fungal spore levels were detected in suburban areas, compared to urban (10). Ulocladium spores contributed to 3.72% of the total catch during a 2-year study and reached a peak during spring, from February to May (11). In another study, the peak spore concentration was in winter, followed by spring (12).
Taxonomy
Taxonomic tree of Alternaria genus (1, 13)
|
---|
Domain
|
Eukaryota
|
Kingdom
|
Fungi
|
Phylum
|
Ascomycota
|
Subphylum
|
Pezizomycotina
|
Class
|
Dothideomycetes
|
Order
|
Pleosporales
|
Family
|
Pleosporaceae
|
Genus
|
Alternaria
|
Taxonomic tree of Alternaria genus (1, 13)
|
---|
Tissue
Spores release allergens (4).