Aspergillus

Aspergillus (ˌæspərˈdʒɪləs) is a genus consisting of several hundred mould species found in various climates worldwide. Aspergillus was first catalogued in 1729 by the Italian priest and biologist Pier Antonio Micheli. Viewing the fungi under a microscope, Micheli was reminded of the shape of an aspergillum (holy water sprinkler), from Latin spargere (to sprinkle), and named the genus accordingly. Aspergillum is an asexual spore-forming structure common to all Aspergillus species; around one-third of species are also known to have a sexual stage. While some species of Aspergillus are known to cause fungal infections, others are of commercial importance. List of Aspergillus species Aspergillus consists of 837 species of fungi. Aspergillus is defined as a group of conidial fungi—that is, fungi in an asexual state. Some of them, however, are known to have a teleomorph (sexual state) in the Ascomycota. With DNA evidence, all members of the genus Aspergillus are members of the phylum Ascomycota. Members of the genus possess the ability to grow where a high osmotic pressure exists (high concentration of sugar, salt, etc.). Aspergillus species are highly aerobic and are found in almost all oxygen-rich environments, where they commonly grow as molds on the surface of a substrate, as a result of the high oxygen tension. Commonly, fungi grow on carbon-rich substrates like monosaccharides (such as glucose) and polysaccharides (such as amylose). Aspergillus species are common contaminants of starchy foods (such as bread and potatoes), and grow in or on many plants and trees. In addition to growth on carbon sources, many species of Aspergillus demonstrate oligotrophy where they are capable of growing in nutrient-depleted environments, or environments with a complete lack of key nutrients. Aspergillus niger is a prime example of this; it can be found growing on damp walls, as a major component of mildew. Several species of Aspergillus, including A. niger and A. fumigatus, will readily colonise buildings, favouring warm and damp or humid areas such as bathrooms and around window frames.