Dandruff is a skin condition that mainly affects the scalp. Symptoms include flaking and sometimes mild itchiness. It can result in social or self-esteem problems. A more severe form of the condition, which includes inflammation of the skin, is known as seborrhoeic dermatitis.
Tinea versicolor is a condition characterized by a skin eruption on the trunk and proximal extremities. The majority of tinea versicolor is caused by the fungus Malassezia globosa, although Malassezia furfur is responsible for a small number of cases. These yeasts are normally found on the human skin and become troublesome only under certain circumstances, such as a warm and humid environment, although the exact conditions that cause initiation of the disease process are poorly understood.
Seborrhoeic dermatitis, also known as seborrhoea, is a long-term skin disorder. Symptoms include red, scaly, greasy, itchy, and inflamed skin. Areas of the skin rich in oil-producing glands are often affected including the scalp, face, and chest. It can result in social or self-esteem problems. In babies, when the scalp is primarily involved, it is called cradle cap. Dandruff is a milder form of the condition without inflammation.
Malassezia is a genus of fungi. Malassezia is naturally found on the skin surfaces of many animals, including humans. In occasional opportunistic infections, some species can cause hypopigmentation or hyperpigmentation on the trunk and other locations in humans. Allergy tests for this fungus are available.
Malassezia furfur is a species of yeast that is naturally found on the skin surfaces of humans and some other mammals. It is associated with a variety of dermatological conditions caused by fungal infections, notably seborrhoeic dermatitis and tinea versicolor. As an opportunistic pathogen, it has further been associated with dandruff, malassezia folliculitis, pityriasis versicolor (alba), and malassezia intertrigo, as well as catheter-related fungemia and pneumonia in patients receiving hematopoietic transplants. The fungus can also affect other animals, including dogs.
Exophiala jeanselmei is a saprotrophic fungus in the family Herpotrichiellaceae. Four varieties have been discovered: Exophiala jeanselmei var. heteromorpha, E. jeanselmei var. lecanii-corni, E. jeanselmei var. jeanselmei, and E. jeanselmei var. castellanii. Other species in the genus Exophiala such as E. dermatitidis and E. spinifera have been reported to have similar annellidic conidiogenesis and may therefore be difficult to differentiate.
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. Proliferation of Trichosporon yeasts in the hair can lead to an unpleasant but non-serious condition known as white piedra. Trichosporon species can also cause severe opportunistic infections (trichosporonosis) in immunocompromised individuals.
Malassezia folliculitis or Pityrosporum folliculitis, is a skin condition caused by infection by Malassezia yeast.
In bio-informatics, a peptide-mass fingerprint or peptide-mass map is a mass spectrum of a mixture of peptides that comes from a digested protein being analyzed. The mass spectrum serves as a fingerprint in the sense that it is a pattern that can serve to identify the protein. The method for forming a peptide-mass fingerprint, developed in 1993, consists of isolating a protein, breaking it down into individual peptides, and determining the masses of the peptides through some form of mass spectrometry. Once formed, a peptide-mass fingerprint can be used to search in databases for related protein or even genomic sequences, making it a powerful tool for annotation of protein-coding genes.
Staphylococcus intermedius is a Gram-positive, catalase positive member of the bacterial genus Staphylococcus consisting of clustered cocci. Strains of this species were originally isolated from the anterior nares of pigeons, dogs, cats, mink, and horses. Many of the isolated strains show coagulase activity. Clinical tests for detection of methicillin-resistant S. aureus may produce false positives by detecting S. intermedius, as this species shares some phenotypic traits with methicillin-resistant S. aureus strains. It has been theorized that S. intermedius has previously been misidentified as S. aureus in human dog bite wound infections, which is why molecular technologies such as MALDI-TOF and PCR are preferred in modern veterinary clinical microbiology laboratories for their more accurate identifications over biochemical tests. S. intermedius is largely phenotypically indiscriminate from Staphylococcus pseudintermedius and Staphylococcus delphini, and therefore the three organisms are considered to be included in the more general 'Staphylococcus intermedius group'.
Exophiala dermatitidis is a thermophilic black yeast, and a member of the Herpotrichiellaceae. While the species is only found at low abundance in nature, metabolically active strains are commonly isolated in saunas, steam baths, and dish washers. Exophiala dermatitidis only rarely causes infection in humans, however cases have been reported around the world. In East Asia, the species has caused lethal brain infections in young and otherwise healthy individuals. The fungus has been known to cause cutaneous and subcutaneous phaeohyphomycosis, and as a lung colonist in people with cystic fibrosis in Europe. In 2002, an outbreak of systemic E. dermatitidis infection occurred in women who had received contaminated steroid injections at North Carolina hospitals.
Malassezia japonica is a fungus that can cause opportunistic infections in animals.
Malassezia nana is a fungus that can cause opportunistic infections in animals. It was first isolated from animals in Japan and Brazil. M. nana resembles M. dermatis and M. sympodialis, but is distinguished from these species by its inability to use Kolliphor EL (Sigma) as the sole lipid source and to hydrolyse aesculin. The type strain of M. nana is NUSV 1003T(=CBS 9557T=JCM 12085T).
Staphylococcus pseudintermedius is a gram positive coccus bacteria of the genus Staphylococcus found worldwide. It is primarily a pathogen for domestic animals, but has been known to affect humans as well.S. pseudintermedius is an opportunistic pathogen that secretes immune modulating virulence factors, has many adhesion factors, and the potential to create biofilms, all of which help to determine the pathogenicity of the bacterium. Diagnoses of Staphylococcus pseudintermedius have traditionally been made using cytology, plating, and biochemical tests. More recently, molecular technologies like MALDI-TOF, DNA hybridization and PCR have become preferred over biochemical tests for their more rapid and accurate identifications. This includes the identification and diagnosis of antibiotic resistant strains.
Malassezia pachydermatis is a zoophilic yeast in the division Basidiomycota. It was first isolated in 1925 by Fred Weidman, and has been named pachydermatis Greek for "thick-skin" after the original sample taken from an Indian rhinoceros with severe exfoliative dermatitis. Within the genus Malassezia, M. pachydermatis is most closely related to the species M. furfur. A commensal fungus, it can be found within the microflora of healthy mammals such as humans, cats and dogs, However, it is capable of acting as an opportunistic pathogen under special circumstances and has been seen to cause skin and ear infections, most often occurring in canines.
Histoplasma duboisii is a saprotrophic fungus responsible for the invasive infection known as African histoplasmosis. This species is a close relative of Histoplasma capsulatum, the agent of classical histoplasmosis, and the two occur in similar habitats. Histoplasma duboisii is restricted to continental Africa and Madagascar, although scattered reports have arisen from other places usually in individuals with an African travel history. Like, H. capsulatum, H. duboisii is dimorphic – growing as a filamentous fungus at ambient temperature and a yeast at body temperature. It differs morphologically from H. capsulatum by the typical production of a large-celled yeast form. Both agents cause similar forms of disease, although H. duboisii predominantly causes cutaneous and subcutaneous disease in humans and non-human primates. The agent responds to many antifungal drug therapies used to treat serious fungal diseases.
Malassezia sympodialis is a species in the genus Malassezia. It is characterized by a pronounced lipophily, unilateral, percurrent or sympodial budding and an irregular, corrugated cell wall ultrastructure. It is one of the most common species found on the skin of healthy and diseased individuals. It is considered to be part of the skin's normal human microbiota and begins to colonize the skin of humans shortly after birth. Malassezia sympodialis, often has a symbiotic or commensal relationship with its host, but it can act as a pathogen causing a number of different skin diseases, such as atopic dermatitis.
Exophiala phaeomuriformis is thermophilic fungus belonging to the genus Exophiala and the family Herpotrichiellaceae. it is a member of the group of fungi known as black yeasts, and is typically found in hot and humid locations, such as saunas, bathrooms, and dishwashers. This species can cause skin infections and is typically classified as a Biosafety Risk Group 2 agent.
Candida auris is a species of fungus that grows as yeast. It is one of the few species of the genus Candida which cause candidiasis in humans. Often, candidiasis is acquired in hospitals by patients with weakened immune systems. C. auris can cause invasive candidiasis (fungemia) in which the bloodstream, the central nervous system, and internal organs are infected. It has attracted widespread attention because of its multiple drug resistance. Treatment is also complicated because it is easily misidentified as other Candida species.
Sarocladium kiliense is a saprobic fungus that is occasionally encountered as a opportunistic pathogen of humans, particularly immunocompromised and individuals. The fungus is frequently found in soil and has been linked with skin and systemic infections. This species is also known to cause disease in the green alga, Cladophora glomerata as well as various fruit and vegetable crops grown in warmer climates.
