Balamuthia mandrillaris: Difference between revisions
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==Cell Structure, Metabolism and Life Cycle== | ==Cell Structure, Metabolism and Life Cycle== | ||
The cell structure of B. mandrillaris is characterized by a distinctive amoeboid form with a central granular endoplasm and a clear ectoplasm, enabling motility and phagocytosis. B. mandrillaris exhibits a unique multilayered cell wall, a distinguishing feature among free-living amoebas, which likely contributes to its resilience and virulence in causing infections (Khan & Siddiqui 2015). | |||
B. mandrillaris is a heterotrophic amoeba, relying on external food sources for energy. The organism gains energy through phagocytosis, actively ingesting bacteria and other particles. As part of its metabolic activity, B. mandrillaris produces molecules such as adenosine triphosphate (ATP), reflecting its capacity for cellular energy generation during the trophozoite stage (Feldman & Yohannan 2019). | |||
The life cycle of Balamuthia mandrillaris involves a trophic amoeboid stage and a cystic stage, both of which are infectious. During the trophic stage it actively feeds on bacteria for metabolic purposes. The trophozoite is pleomorphic and uninucleated, but rarely can be binucleated. The crucial transition occurs when the amoeba transforms into a dormant cyst, enabling its survival in adverse conditions. During the cyst stage, B. mandrillaris produces a protective outer ectocyst layer, and the cysts serve as the main infectious form responsible for the transmission of the pathogen (Khan & Siddiqui 2015). | |||
==Ecology and Pathogenesis== | ==Ecology and Pathogenesis== | ||
Revision as of 23:40, 16 November 2023
Classification
Eukaryota; Amoebozoa; Discosea; longamoebia; Balamuthiidae
Species
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NCBI: [1] |
Balamuthia mandrillaris
Description and Significance
Balamuthia mandrillaris, a free-living amoeba, is the causative agent of the rare yet fatal neurological condition known as granulomatous amoebic encephalitis (GAE). Discovered in 1986 within the brain of a deceased mandrill at the San Diego Wild Animal Park. The pathogen was successfully isolated and studied for the first time in 1993 by Govinda Visvesvara, paying tribute to his mentor William Balamuth for his amoebae research. (Cope et al.,2019)
B. mandrillaris primarily dwells in soil and poses a great threat to human health. This amoeba can invade the human body through open wounds or inhalation, and it has been isolated from soil samples. Believed to be found across temperate regions globally, evidence supporting this includes the detection of antibodies to the protist in the bloodstream of healthy individuals (Schuster et al.,2003).
Genome Structure
The genome of Balamuthia mandrillaris is characterized by its complexity and unique features. B. mandrillaris possesses a relatively large genome with multiple chromosomes. The specific number of chromosomes is not mentioned but it may vary between different strains. The genome is circular, which is a common feature among amoebas. The draft genome highlights the importance of reference genome sequencing for this pathogen, emphasizing the ongoing efforts to assemble a comprehensive and accurate genomic sequence.
Cell Structure, Metabolism and Life Cycle
The cell structure of B. mandrillaris is characterized by a distinctive amoeboid form with a central granular endoplasm and a clear ectoplasm, enabling motility and phagocytosis. B. mandrillaris exhibits a unique multilayered cell wall, a distinguishing feature among free-living amoebas, which likely contributes to its resilience and virulence in causing infections (Khan & Siddiqui 2015).
B. mandrillaris is a heterotrophic amoeba, relying on external food sources for energy. The organism gains energy through phagocytosis, actively ingesting bacteria and other particles. As part of its metabolic activity, B. mandrillaris produces molecules such as adenosine triphosphate (ATP), reflecting its capacity for cellular energy generation during the trophozoite stage (Feldman & Yohannan 2019).
The life cycle of Balamuthia mandrillaris involves a trophic amoeboid stage and a cystic stage, both of which are infectious. During the trophic stage it actively feeds on bacteria for metabolic purposes. The trophozoite is pleomorphic and uninucleated, but rarely can be binucleated. The crucial transition occurs when the amoeba transforms into a dormant cyst, enabling its survival in adverse conditions. During the cyst stage, B. mandrillaris produces a protective outer ectocyst layer, and the cysts serve as the main infectious form responsible for the transmission of the pathogen (Khan & Siddiqui 2015).
Ecology and Pathogenesis
Habitat; symbiosis; biogeochemical significance; contributions to environment.
If relevant, how does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms.
References
1. Cope, Jennifer R.; Landa, Janet; Nethercut, Hannah; Collier, Sarah A.; Glaser, Carol; Moser, Melanie; Puttagunta, Raghuveer; Yoder, Jonathan S.; Ali, Ibne K.; Roy, Sharon L. (2019-05-17). "The Epidemiology and Clinical Features of Balamuthia mandrillaris Disease in the United States, 1974 – 2016". Clinical Infectious Diseases. 68 (11): 1815–1822. doi:10.1093/cid/ciy813. ISSN 1058-4838. PMC 7453664. PMID 30239654.
2. Frederick L. Schuster; Thelma H. Dunnebacke; Gregory C. Booton; Shigeo Yagi; Candice K. Kohlmeier; Carol Glaser; Duc Vugia; Anna Bakardjiev; Parvin Azimi; Mary Maddux-Gonzalez; A. Julio Martinez; Govinda S. Visvesvara (July 2003). "Environmental Isolation of Balamuthia mandrillaris Associated with a Case of Amebic Encephalitis". J. Clin. Microbiol. 41 (7): 3175–3180. doi:10.1128/JCM.41.7.3175-3180.2003. PMC 165348. PMID 12843060.
3. Greninger, Alexander L.; Messacar, Kevin; Dunnebacke, Thelma; Naccache, Samia N.; Federman, Scot; Bouquet, Jerome; Mirsky, David; Nomura, Yosuke; Yagi, Shigeo; Glaser, Carol; Vollmer, Michael; Press, Craig A.; Kleinschmidt-DeMasters, Bette K.; Dominguez, Samuel R.; Chiu, Charles Y. (2015). "Clinical metagenomic identification of Balamuthia mandrillaris encephalitis and assembly of the draft genome: the continuing case for reference genome sequencing". Genome Medicine. 7 (1): 113. doi:10.1186/s13073-015-0235-2. ISSN 1756-994X. PMC 4665321. PMID 26620704.
Author
Page authored by Bella Readling, student of Prof. Bradley Tolar at UNC Wilmington.
