Trichosporon beigelii
Encyclopedia
Trichosporon beigelii is a species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of fungus
Fungus
A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds , as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from plants, animals, and bacteria...

 in the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Trichosporonaceae. It is a yeast
Yeast
Yeasts are eukaryotic micro-organisms classified in the kingdom Fungi, with 1,500 species currently described estimated to be only 1% of all fungal species. Most reproduce asexually by mitosis, and many do so by an asymmetric division process called budding...

 that was formerly considered to be the cause of an unpleasant hair condition called white piedra
White piedra
White piedra is a mycosis of the hair caused by several species of fungi in the genus Trichosporon. It is characterized by soft nodules composed of yeast cells and arthroconidia that encompass hair shafts.-Treatment:...

and also the cause of a more serious severe opportunistic infection
Opportunistic infection
An opportunistic infection is an infection caused by pathogens, particularly opportunistic pathogens—those that take advantage of certain situations—such as bacterial, viral, fungal or protozoan infections that usually do not cause disease in a healthy host, one with a healthy immune system...

 (trichosporonosis
Trichosporonosis
Trichosporonosis is a systemic disease associated with fungi in the genus Trichosporon.It can appear in patients who are immunosuppressed....

) in immunocompromised individuals. Recent research, however, has shown that several Trichosporon
Trichosporon
Trichosporon is a genus of anamorphic fungi in the family Trichosporonaceae. All species of Trichosporon are yeasts with no known teleomorphs . Most are typically isolated from soil, but several species occur as a natural part of the skin microbiota of humans and other animals...

species are involved in these infections. Since it is unclear to which of these species the name Trichosporon beigelii should be applied, the name is now considered obsolete.

History

The species was first described in 1867 from the hairs of a wig by Friedrich Küchenmeister
Friedrich Küchenmeister
Gottlieb Heinrich Friedrich Küchenmeister was a German physician.- Life :...

 and Rabenhorst
Gottlob Ludwig Rabenhorst
Gottlob Ludwig Rabenhorst was a German botanist. He was a student in Berlin and Belzig from 1822 to 1830, a pharmacist in Luckau until 1840, and received his doctorate in Jena in 1841. Rabenhorst edited the scientific journal Hedwigia from 1852 to 1878....

. They thought that the organism was an alga and placed it in the genus Pleurococcus
Pleurococcus
Pleurococcus is a genus of algae, in the family Chaetophoraceae. Purported to be the most abundant creature on the planet at ten trillion trillion. They can be found growing on moist, dark patches of trees, rocks and soil. They can be found alone or in bunches together forming a slimy layer...

. The French mycologist Vuillemin
Jean Paul Vuillemin
Jean Paul Vuillemin was a French mycologist.He studied medicine at the University of Nancy in 1884, and from 1895 to 1932 he was Professor of Natural History at the medical faculty there. He described the genera Spinalia and Zygorhynchus....

 later realized it was a yeast
Yeast
Yeasts are eukaryotic micro-organisms classified in the kingdom Fungi, with 1,500 species currently described estimated to be only 1% of all fungal species. Most reproduce asexually by mitosis, and many do so by an asymmetric division process called budding...

 and transferred it to the genus Trichosporon, considering it to be synonymous with Trichosporon ovoides.

Trichosporon beigelii was widely assumed to be the causative agent of white piedra
White piedra
White piedra is a mycosis of the hair caused by several species of fungi in the genus Trichosporon. It is characterized by soft nodules composed of yeast cells and arthroconidia that encompass hair shafts.-Treatment:...

 in humans and other animals until the advent of DNA sequencing
DNA sequencing
DNA sequencing includes several methods and technologies that are used for determining the order of the nucleotide bases—adenine, guanine, cytosine, and thymine—in a molecule of DNA....

, when it became clear that more than one Trichosporon species could cause the infection. McPartland & Goff selected a neotype strain that made T. beigelii synonymous with T. cutaneum. Guého and others, however, selected a neotype strain that made T. beigelii synonymous with T. ovoides. Since it is not clear to which of these (or other Trichosporon species) the name T. beigelii should be applied, the name is now considered to be of uncertain application and hence obsolete.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK