Malassezia is a genus of fungi (specifically, a yeast).

Malassezia
Malassezia furfur in skin scale from a patient with tinea versicolor
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Fungi
Division: Basidiomycota
Subdivision: Ustilaginomycotina
Class: Malasseziomycetes
Denchev & T.Denchev (2014)
Order: Malasseziales
R.T.Moore (1980)
Family: Malasseziaceae
Denchev & R.T.Moore (2009)
Genus: Malassezia
Baill. (1889)[1]
Type species
Malassezia furfur
(C.P.Robin) Baill. (1889)
Synonyms[2]

Some species of Malassezia are found on the skin of animals, including humans. Because malassezia requires fat to grow,[3] it is most common in areas with many sebaceous glands—on the scalp,[4] face, and upper part of the body.

Role in human diseases

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Malassezia infections of human skin can cause or aggravate a variety of conditions, including dandruff, seborrheic dermatitis, and acne.[5]

Dermatitis and dandruff

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When Malassezia grows too rapidly, the natural renewal of cells is disturbed, and dandruff can appear with itching (a similar process may also occur with other fungi or bacteria).

Identification of Malassezia on skin has been aided by the application of molecular or DNA-based techniques. These investigations show that the M. globosa is the species that causes most skin disease in humans, and that it is the most common cause of dandruff and seborrhoeic dermatitis (though M. restricta is also involved).[6]

There can be as many as ten million M. globosa organisms on a human head.[4]

A project in 2007 sequenced the genome of dandruff-causing Malassezia globosa and found it to have 4,285 genes.[7][8] M. globosa uses eight different types of lipase, along with three phospholipases, to break down the oils on the scalp. Any of these 11 proteins would be a suitable target for dandruff medications.

Prescription and over-the-counter shampoos containing ketoconazole are commonly used to treat dandruff caused by Malassezia.

M. globosa has been predicted to have the ability to reproduce sexually,[9] but this has not been observed.

Skin pigmentation disorders

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In occasional opportunistic infections of the trunk and other locations on humans, some species of Malassezia can cause hypopigmentation or hyperpigmentation. Allergy tests for these fungi are available.

The skin rash of tinea versicolor (pityriasis versicolor) is also caused by an infection of this fungus.[10]

Cancer

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Translocation of Malassezia species from the intestines into pancreatic neoplasms has been associated with pancreatic ductal adenocarcinoma, and the fungi may promote tumor progression through activation of host complement.[11][12]

Crohn's and inflammatory bowel disease

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M. restricta, which is normally found in the skin, is linked to disorders like Crohn's disease and inflammatory bowel disease when found in the gut. This is especially true for organism with the N12 CARD9 allele, which provokes a stronger inflammatory response.[13]

Malassezia folliculitis

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A 25-year-old man with pityrosporum folliculitis and electron micrograph of his skin, showing Malassezia spores.[14]

Malassezia folliculitis (also called pityrosporum folliculitis),[15] is caused by infection with Malassezia.[16]

Systematics

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Malassezia is the sole genus in family Malasseziaceae, which is the only family in order Malasseziales, itself the single member of class Malasseziomycetes.[17]

Due to progressive changes in their nomenclature, some confusion exists about the naming and classification of Malassezia yeast species. Work on these yeasts has been complicated because they require specific growth media and sometimes grow very slowly in laboratory culture.[18]

Malassezia was originally identified by the French scientist Louis-Charles Malassez in the late nineteenth century;[19] he associated it with the condition seborrhoeic dermatitis.[20] Raymond Sabouraud identified a dandruff-causing organism in 1904 and called it Pityrosporum Malassezii,[21] honoring Malassez, but at the species level as opposed to the genus level. When it was determined that the organisms were the same, the term "Malassezia" was judged to possess priority.[22]

In the mid-twentieth century, it was reclassified into two species:

  • Pityrosporum (Malassezia) ovale, which is lipid-dependent and found only on humans. P. ovale was later divided into two species, P. ovale and P. orbiculare, but current sources consider these terms to refer to a single species of fungus, with M. furfur the preferred name.[23]
  • Pityrosporum (Malassezia) pachydermatis, which is lipophilic but not lipid-dependent. It is found on the skin of most animals.

Malassezia is the sole genus in the family Malasseziaceae, which was validated by Cvetomir Denchev and Royall T. Moore in 2009.[24] The order Malasseziales had been previously proposed by Moore in 1980,[25] and later emended by Begerow and colleagues in 2000. At this time the order was classified as a member of unknown class placement in the subdivision Ustilaginomycotina.[26] In 2014, Cvetomir and Teodor Denchev circumscribed the class Malasseziomycetes to contain the group.[27]

Description

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Malassezia grows rapidly, typically maturing within 5 days when incubated at temperatures ranging from 30–35 °C (86–95 °F). Growth is slower at 25 °C (77 °F), and certain species struggle at 37 °C (99 °F). These organisms can proliferate on media infused with cycloheximide. An essential factor for the growth of Malassezia is the presence of long-chain fatty acids, with M. pachydermatis being an exception. The most conventional cultivation method involves overlaying solid media with a layer of olive oil. However, for nurturing some clinically relevant species, such as the challenging-to-cultivate M. restricta, more intricate culture media may be required. For the most efficient recovery of Malassezia, it has been recommended to collect blood through a lipid infusion catheter and subsequently use lysis-centrifugation—a recommendation backed by multiple comparative studies.[28]

The yeast-like cells of Malassezia, measuring between 1.5–4.5 μm by 3–7 μm, are characterised as phialides featuring tiny collarettes (a small, collar-like flange or lip at the mouth of a phialide from which spores or conidia are produced and released). These collarettes are challenging to identify using standard light microscopes. A defining characteristic of cells from this genus is their morphology: one end is round, while the other has a distinctly blunt termination. This latter end is where singular, broad-based bud-like structures emerge, although in certain species, these structures might be narrower. To effectively visualise the organism's shape, a staining technique involving safranin is recommended, followed by observation under oil immersion. Furthermore, Calcofluor-white staining provides an enhanced clarity of the cell wall and its unique contour. While Malassezia typically lacks hyphal elements, rudimentary forms can sporadically be present.[28]

Species

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The Index Fungorum lists 22 species of Malassezia.[29] The following list gives the name, the taxonomic authority (those who first described the fungus, or who transferred it into Malassezia from another genus; standardized author abbreviations are used), and the name of the organism from which the fungus was isolated, if not human.

In the mid-1990s, scientists at the Pasteur Institute in Paris, France, discovered additional species.[3]

References

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  1. ^ Baillon, H. (1889). Traité de botanique médicale cryptogamique, suivi du tableau du droguier de la Faculté de médecine de Paris, par H. Baillon. Avec 370 figures dans le texte, dessins de A. Faguet [Treatise on cryptogamic medical botany, followed by the druggist's table from the Faculty of Medicine of Paris] (in French). p. 234. doi:10.5962/bhl.title.5409. OCLC 2139870.
  2. ^ "Synonymy: Malassezia Baill., Traité Bot. Méd. Crypt.: 234 (1889)". Species Fungorum. Archived from the original on 16 July 2021. Retrieved 2 April 2021.
  3. ^ a b Guého E, Midgley G, Guillot J (May 1996). "The genus Malassezia with description of four new species". Antonie van Leeuwenhoek. 69 (4): 337–355. doi:10.1007/BF00399623. PMID 8836432. S2CID 31791799.
  4. ^ a b "Genetic code of dandruff cracked". BBC News. BBC. 2007-11-06. Archived from the original on 2008-12-22. Retrieved 2008-12-10.
  5. ^ "Skin conditions associated with malassezia".
  6. ^ a b DeAngelis YM, Saunders CW, Johnstone KR, et al. (September 2007). "Isolation and expression of a Malassezia globosa lipase gene, LIP1". J. Invest. Dermatol. 127 (9): 2138–46. doi:10.1038/sj.jid.5700844. PMID 17460728.
  7. ^ Xu J, Saunders CW, Hu P, et al. (November 2007). "Dandruff-associated Malassezia genomes reveal convergent and divergent virulence traits shared with plant and human fungal pathogens". Proc. Natl. Acad. Sci. U.S.A. 104 (47): 18730–5. Bibcode:2007PNAS..10418730X. doi:10.1073/pnas.0706756104. PMC 2141845. PMID 18000048.
  8. ^ Spectrum Science Public Relations (21 November 2007). "Scientists Complete Genome Sequence Of Fungus Responsible For Dandruff, Skin Disorders". ScienceDaily. Archived from the original on 28 December 2007. Retrieved 5 February 2023.
  9. ^ Guillot J, Hadina S, Guého E (June 2008). "The genus Malassezia: old facts and new concepts". Parassitologia. 50 (1–2): 77–9. PMID 18693563.
  10. ^ Saunte, Ditte M.L.; Gaitanis, George; Hay, Roderick James (2020). "Malassezia-associated skin diseases, the use of diagnostics and treatment". Frontiers in Cellular and Infection Microbiology. 10: 1–11. doi:10.3389/fcimb.2020.00112. PMC 7098993. PMID 32266163.
  11. ^ Aykut B, Pushalkar S, Chen R, Li Q, Abengozar R, Kim JI, et al. (2019). "The fungal mycobiome promotes pancreatic oncogenesis via activation of MBL". Nature. 574 (7777): 264–267. Bibcode:2019Natur.574..264A. doi:10.1038/s41586-019-1608-2. PMC 6858566. PMID 31578522.
  12. ^ Loker, Eric S.; Hofkin, Bruce V. (2023). Parasitology: A Conceptual Approach (Second ed.). Boca Raton: CRC Press. p. 54. doi:10.1201/9780429277405. ISBN 9780429277405. LCCN 2021045732. S2CID 250473493.
  13. ^ Limon, Jose J.; Tang, Jie; Li, Dalin; Wolf, Andrea J.; Michelsen, Kathrin S.; Funari, Vince; Gargus, Matthew; Nguyen, Christopher; Sharma, Purnima; Maymi, Viviana I.; Iliev, Iliyan D.; Skalski, Joseph H.; Brown, Jordan; Landers, Carol; Borneman, James; Braun, Jonathan; Targan, Stephan R.; McGovern, Dermot P.B.; Underhill, David M. (March 2019). "Malassezia Is Associated with Crohn's Disease and Exacerbates Colitis in Mouse Models". Cell Host & Microbe. 25 (3): 377–388.e6. doi:10.1016/j.chom.2019.01.007. PMC 6417942. PMID 30850233.
  14. ^ Ran Yuping (2016). "Observation of Fungi, Bacteria, and Parasites in Clinical Skin Samples Using Scanning Electron Microscopy". In Janecek, Milos; Kral, Robert (eds.). Modern Electron Microscopy in Physical and Life Sciences. InTech. doi:10.5772/61850. ISBN 978-953-51-2252-4. S2CID 53472683.
  15. ^ Rapini, Ronald P.; Bolognia, Jean L.; Jorizzo, Joseph L. (2007). Dermatology: 2-Volume Set. St. Louis: Mosby. ISBN 978-1-4160-2999-1.
  16. ^ James, William D.; Berger, Timothy G.; et al. (2006). Andrews' Diseases of the Skin: clinical Dermatology. Saunders Elsevier. ISBN 0-7216-2921-0.
  17. ^ Wijayawardene, Nalin; Hyde, Kevin; Al-Ani, Laith Khalil Tawfeeq; Somayeh, Dolatabadi; Stadler, Marc; Haelewaters, Danny; et al. (2020). "Outline of Fungi and fungus-like taxa". Mycosphere. 11: 1060–1456. doi:10.5943/mycosphere/11/1/8. hdl:10481/61998.
  18. ^ Theelen, Bart; Cafarchia, Claudia; Gaitanis, Georgios; Bassukas, Ioannis Dimitrios; Boekhout, Teun; Dawson, Thomas L. (2018). "Malassezia ecology, pathophysiology, and treatment". Medical Mycology. 56 (suppl 1): S10–S25. doi:10.1093/mmy/myx134. hdl:11586/215288. PMID 29538738.
  19. ^ Malassez, L. (1874). "Note sur le champignon du pityriasis simple" [Note on the fungus of simple pityriasis]. Archives of Physiology and Biochemistry (in French). 2: 451–464.
  20. ^ Dawson, Thomas L. (2019). "Malassezia: The Forbidden Kingdom Opens". Cell Host Microbe. 25 (3): 345–347. doi:10.1016/j.chom.2019.02.010. PMID 30870616.
  21. ^ Sabouraud, R. (1904). Maladies du cuir chevelu: II. Les maladies desquamatives [Scalp conditions: II. Desquamative disorders] (in French). Paris: Masson et Cie. p. 646.
  22. ^ Inamadar AC, Palit A (2003). "The genus Malassezia and human disease". Indian J Dermatol Venereol Leprol. 69 (4): 265–70. PMID 17642908.
  23. ^ Freedberg; et al., eds. (2003). Fitzpatrick's Dermatology in General Medicine (6th ed.). McGraw-Hill. p. 1187. ISBN 0-07-138067-1.
  24. ^ Denchev, C.M.; Moore, R.T. (2009). "Validation of Malasseziaceae and Ceraceosoraceae (Exobasidiomycetes)". Mycotaxon. 110: 379–382. doi:10.5248/110.379.
  25. ^ Moore, R.T. (1980). "Taxonomic proposals for the classification of marine yeasts and other yeast-like fungi including the smuts". Botanica Marina. 23 (6): 361–373.
  26. ^ Begerow, Dominik; Bauer, Robert; Boekhout, Teun (2000). "Phylogenetic placements of ustilaginomycetous anamorphs as deduced from nuclear LSU rDNA sequences". Mycological Research. 104 (1): 53–60. doi:10.1017/s0953756299001161.
  27. ^ Denchev, C.M.; Denchev, T.T. (2014). "Nomenclatural novelties" (PDF). Index Fungorum. 145: 1. Archived (PDF) from the original on 2015-02-06. Retrieved 2021-12-06.
  28. ^ a b Larone, Davise Honig (2011). Medically Important Fungi (5th ed.). Washington (D.C.): ASM press. p. 146. ISBN 978-1-55581-660-5.
  29. ^ Species Fungorum. "Malassezia". Catalog of Life. Archived from the original on 3 November 2022. Retrieved 23 September 2022.
  30. ^ Honnavar, P.; Prasad, G.S.; Ghosh, A.; Dogra, S.; Handa, S.; Rudramurthy, S.M. (2016). "Malassezia arunalokei sp. nov., a novel yeast species isolated from seborrhoeic dermatitis patients and healthy individuals from India". Journal of Clinical Microbiology. 54 (7): 1826–1834. doi:10.1128/JCM.00683-16. PMC 4922115. PMID 27147721.
  31. ^ Cabañes, F.J.; Coutinho, S.D.A.; Puig, L.; Bragulat, M.R.; Castellá, G. (2016). "New lipid-dependent Malassezia species from parrots". Revista Iberoamericana de Micología. 33 (2): 92–99. doi:10.1016/j.riam.2016.03.003. PMID 27184440.
  32. ^ a b Cabañes, F. Javier; Theelen, Bart; Castellá, Gemma; Boekhout, Teun (September 2007). "Two new lipid-dependent Malassezia species from domestic animals". FEMS Yeast Research. 7 (6): 1064–1076. doi:10.1111/j.1567-1364.2007.00217.x. PMID 17367513.
  33. ^ Cabañes FJ, Vega S, Castellá G (2011). "Malassezia cuniculi sp. nov., a novel yeast species isolated from rabbit skin". Medical Mycology. 49 (1): 40–48. doi:10.3109/13693786.2010.493562. PMID 20560865.
  34. ^ Sugita T, Takashima M, Shinoda T, et al. (April 2002). "New Yeast Species, Malassezia dermatis, Isolated from Patients with Atopic Dermatitis". J. Clin. Microbiol. 40 (4): 1363–7. doi:10.1128/JCM.40.4.1363-1367.2002. PMC 140359. PMID 11923357.
  35. ^ White, S.D.; Vandenabeele, S.I.J.; Drazenovich, N.L.; Foley, J.E. (March 2006). "Malassezia Species Isolated from the Intermammary and Preputial Fossa Areas of Horses". Journal of Veterinary Internal Medicine. 20 (2): 395–398. doi:10.1111/j.1939-1676.2006.tb02874.x. PMID 16594600.
  36. ^ Sugita, Takashi; Masako Takashima; Minako Kodama; Ryoji Tsuboi; Akemi Nishikawa (October 2003). "Description of a New Yeast Species, Malassezia japonica, and Its Detection in Patients with Atopic Dermatitis and Healthy Subjects". J. Clin. Microbiol. 41 (10): 4695–4699. doi:10.1128/JCM.41.10.4695-4699.2003. PMC 254348. PMID 14532205.
  37. ^ Hirai A, Kano R, Makimura K, et al. (March 2004). "Malassezia nana sp. nov., a novel lipid-dependent yeast species isolated from animals". Int. J. Syst. Evol. Microbiol. 54 (Pt 2): 623–7. doi:10.1099/ijs.0.02776-0. PMID 15023986.
  38. ^ Guého, E.; Midgley, G.; Guillot, J. (1996). "The genus Malassezia with description of four new species". Antonie van Leeuwenhoek. 69 (4): 337–355. doi:10.1007/BF00399623. PMID 8836432. S2CID 31791799.
  39. ^ Maecke, Margarita (1941). "Descripción de una nueva especie de Malassezia: Malassezia ochoterenai, agente causal de Pytiriasis (Tinea) vesicolor y posición sistemática del género Malassezia". Anales del Instituto de Biología (in Spanish). 12: 511–546.
  40. ^ Coutinho SD, Paula CR (June 1998). "Biotyping of Malassezia pachydermatis strains using the killer system". Rev Iberoam Micol. 15 (2): 85–7. PMID 17655416.
  41. ^ Lorch JM, Palmer JM, Vanderwolf KJ, et al. (2018). "Malassezia vespertilionis sp. nov. :a new cold-tolerant species of yeast isolated from bats". Persoonia. 41: 56–70. doi:10.3767/persoonia.2018.41.04. PMC 6344816. PMID 30728599. Archived from the original on 2018-07-19. Retrieved 2019-09-18.
  42. ^ Sugita T, Tajima M, Amaya M, Tsuboi R, Nishikawa A (2004). "Genotype analysis of Malassezia restricta as the major cutaneous flora in patients with atopic dermatitis and healthy subjects". Microbiol. Immunol. 48 (10): 755–9. doi:10.1111/j.1348-0421.2004.tb03601.x. PMID 15502408.
  43. ^ Uzal FA, Paulson D, Eigenheer AL, Walker RL (October 2007). "Malassezia slooffiae-associated dermatitis in a goat". Veterinary Dermatology. 18 (5): 348–52. doi:10.1111/j.1365-3164.2007.00606.x. PMID 17845623.
  44. ^ Niamba P, Weill FX, Sarlangue J, Labrèze C, Couprie B, Taïeh A (August 1998). "Is common neonatal cephalic pustulosis (neonatal acne) triggered by Malassezia sympodialis?". Arch Dermatol. 134 (8): 995–8. doi:10.1001/archderm.134.8.995. PMID 9722730.
  45. ^ Lorch, J.M.; Palmer, J.M.; Vanderwolf, K.J.; Schmidt, K.Z.; Verant, M.L.; Weller, T.J.; Blehert, D.S. (2018). "Malassezia vespertilionis sp. nov.: a new cold-tolerant species of yeast isolated from bats". Persoonia - Molecular Phylogeny and Evolution of Fungi. 41 (1): 56–70. doi:10.3767/persoonia.2018.41.04. PMC 6344816. PMID 30728599.
  46. ^ Sugita T, Tajima M, Takashima M, et al. (2004). "A new yeast, Malassezia yamatoensis, isolated from a patient with seborrheic dermatitis, and its distribution in patients and healthy subjects". Microbiol. Immunol. 48 (8): 579–83. doi:10.1111/j.1348-0421.2004.tb03554.x. PMID 15322337. S2CID 34281815.

Further reading

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