Melanized Fungi: Introduction, List of Melanized Fungi, Pathogenecity, and Keynotes
Introduction
Melanized fungi, also known as melanized or black yeasts, are a group of fungi that have the ability to produce melanin, a dark pigment that protects them from environmental stressors such as UV radiation and reactive oxygen species. They are found in a variety of environments, including soil, water, and air, and can also be found as commensal or pathogenic organisms in animals and humans.
They are characterized by their unique cell wall structure, which contains a layer of melanin that gives them their distinctive black coloration. This layer also provides protection against a range of stressors, including extreme temperatures, desiccation, and chemical stressors.
Some melanized fungi have been associated with human diseases, particularly in individuals with compromised immune systems, where they can cause a range of infections such as mycosis, phaeohyphomycosis, and chromoblastomycosis. However, melanized fungi also have various beneficial applications, including the production of antibiotics, enzymes, and other bioactive compounds.
Melanized fungi have been studied extensively due to their unique properties and potential applications in biotechnology, medicine, and environmental remediation.
List of melanized fungi
- Achaetomium
- Acrophialophora
- Alternaria
- Anthopsis
- Arnium
- Arthrinium
- Ascotricha
- Aureobasidium
- Bipolaris
- Botryomyces
- Chaetomium
- Cladophialophora
- Cladorrhinum
- Cladosporium
- Colletotrichum
- Coniothyrium
- Corynespora
- Curvularia
- Cyphellophora
- Dichotomophthora
- Dichotomophthoropsis
- Dissitimurus
- Drechslera
- Exophiala
- Exserohilum
- Fonsecaea
- Hormonema
- Hortaeae
- Lasiodiplodia
- Lecythophora
- Leptosphaeria
- Macrophomina
- Madurella
- Microascus
- Microsphaeropsis
- Myceliophthora
- Mycocentrospora
- Mycoleptodiscus
- Neoscytalidium
- Neotestudina
- Nigrospora
- Ochrocladosporium
- Ochroconis
- Oidiodendron
- Phaeoacremonium
- Phaeosclera
- Phaeotrichoconis
- Phialemonium
- Phialophora
- Piedraia
- Pleurophoma
- Pleurostomophora
- Pseudochaetosphaeronema
- Pseudomicrodochium
- Pyrenochaeta
- Rhinocladiella
- Sarcinomyces
- Scedosporium
- Scopulariopsis
- Sphaeropsis
- Stenella
- Taeniolella
- Tetraploa
- Thermomyces
- Ulocladium
- Veronaea
Pathogenicity
Melanized fungi have the potential to cause infections in humans and animals, particularly in individuals with weakened immune systems. These infections are often chronic and difficult to treat. Melanized fungi are opportunistic pathogens, meaning that they usually only cause infections in individuals with compromised immune systems, such as those with HIV/AIDS, cancer, or who have undergone organ transplantation.
Some of the diseases caused by melanized fungi include chromoblastomycosis, phaeohyphomycosis, and mycosis. Chromoblastomycosis is a chronic infection that affects the skin and subcutaneous tissue, and is caused by several species of melanized fungi such as Fonsecaea pedrosoi and Cladophialophora carrionii. Phaeohyphomycosis is another type of fungal infection that can affect the skin, nails, and soft tissue, and is caused by several different melanized fungi, including Exophiala dermatitidis and Wangiella dermatitidis. Mycosis caused by melanized fungi can involve various organs in the body and may lead to disseminated infections.
The pathogenicity of melanized fungi is due to several factors, including their ability to produce melanin, which helps them to evade the host’s immune system, and their capacity to grow as biofilms, which make them more resistant to antifungal agents.
The treatment of melanized fungal infections can be challenging due to the resistance of these fungi to many antifungal agents. However, some newer antifungal drugs, such as echinocandins and triazoles, have been effective in treating these infections. Early diagnosis and treatment are critical for successful management of melanized fungal infections.
Keynotes
Here are some keynotes on melanized fungi:
- Melanized fungi are a group of fungi that produce melanin, a dark pigment that protects them from environmental stressors.
- They are found in a variety of environments and can be commensal or pathogenic organisms in animals and humans.
- Melanized fungi have a unique cell wall structure that contains a layer of melanin, which provides protection against various stressors, including UV radiation and chemical stressors.
- Some melanized fungi have been associated with human diseases, particularly in individuals with weakened immune systems, where they can cause chronic and difficult-to-treat infections such as chromoblastomycosis and phaeohyphomycosis.
- Melanized fungi are opportunistic pathogens, meaning that they usually only cause infections in individuals with compromised immune systems.
- The pathogenicity of melanized fungi is due to their ability to produce melanin, evade the host’s immune system, and grow as biofilms.
- Treatment of melanized fungal infections can be challenging due to their resistance to many antifungal agents, but newer drugs such as echinocandins and triazoles have shown promise.
- Melanized fungi also have various beneficial applications, including the production of antibiotics, enzymes, and other bioactive compounds, and have been studied extensively for their potential use in biotechnology, medicine, and environmental remediation.
Further Readings
- Revankar, S. G., & Sutton, D. A. (2010). Melanized fungi in human disease. Clinical microbiology reviews, 23(4), 884-928. doi: 10.1128/CMR.00019-10
- Vicente, V. A., Attili-Angelis, D., Pie, M. R., Queiroz-Telles, F., Cruz, L. M., & Najafzadeh, M. J. (2008). Environmental siblings of black agents of human chromoblastomycosis. Fungal biology, 112(8), 855-867. doi: 10.1016/j.funbio.2008.04.008
- Zhang, J., Liu, X., Li, Y., Liang, L., Li, D., Li, X., … & Li, R. (2019). Pathogenicity, virulence factors and strategies for development of control strategies against the emerging fungal pathogen Exophiala dermatitidis. Microbial pathogenesis, 134, 103580. doi: 10.1016/j.micpath.2019.103580
- Gonçalves, S. S., Colombo, A. L., & de Almeida Júnior, J. N. (2017). Dermatophyte and non-dermatophyte fungi in onychomycosis: a review. Mycopathologia, 182(1-2), 1-10. doi: 10.1007/s11046-016-0062-0
- Gorbushina, A. A. (2007). Life on the rocks. Environmental microbiology, 9(7), 1613-1631. doi: 10.1111/j.1462-2920.2007.01301.x