BASIC ONE PAGER

Morphology

Bioprocesses

Taxonomy

The life cycle of Naegleria fowleri passes through three phases:

Naegleria fowleri are a species of protist found in aerobic, aqueous environments. They are thermophilic, halotolerant, hetertrophic, organotrophs, often found praying on bacteria and other microbes. Species of pray include yeast, algae, and gram-negative/positive bacteria. Food selection takes place within the food vacuoles of the cell, and indegestible microbes (e.g. Unicellular Chroococcaceae) are secreted. This species is oppurtunistically parasitic, and will only infect a host if environmental factors demand it. Due to low levels of saturated oxygen in warmer waters, cellular respiration is performed with decreased oxygen consumption during logarithmic growth. Naegleria fowleri reproduces through promitosis during the trophozoite stage.

Kingdom: ProtozoaPhylum: Protozoa Subphylum: Sarcodina Superclass: Rhizopoda Class: Lobosa Order: Amoebida Family: Valkampfidae Genus: Naegleria Species: Naegleria fowleri

Naegleria fowleri

During optimal conditions, Naegleria fowleri exists within the Trophozoite stage. The trophozoites range from 10-15 micrometers long, and consist of a very thin double membrane with granular cytoplasm. Within the cytoplasm is a clear nuclear halo and a dense central nucleus, as well as numerous vacuoles. The trophozoites navigate using lobopodia. When exposed to adverse conditions, Naegleria fowleri can convert into a small cyst of 8-12 micrometers in diameter. These cysts have a smooth, single layered wall, with two pores from which the trophozite will re-emerge. These cysts can survive in conditions ranging from 0-65 degrees celsisus. Within conditions lacking vital nutrients, trophozites can transform into a flagellated form to facilitate quicker movement.

"The Brain Eating Amoeba"

......is a pathogenic amoeba found commonly in bodies of fresh water. Belonging to the Percolozoa phylum, this subspecies of the genus Naegleria is the only of its kind capable of infecting the human body. This microbe causes Primary Amoebic Encephalitis (PAM)--a rare and fatal infection of the brain. Although cases of PAM are currently very rare, Parasitologists worry that Naegleri fowleri will become more prevelant with changing climate conditions.

Sources: (1- image), (2), (6)

Sources: (7), (1), (2)

Pathology

after invasion of the epithelial cells and travel through the olfactory nerves, the amoeba reaches the brain and induces a disease known as PAM (Primary Amoebic Encephalitis). The presence of these microbes within the brain induces severe inflammation, which leads to symtpoms such as seizures, hallucinations, comas, and eventually death. There is no known treatment against this disease, due to the amoeba's highly resistant nature.

Naegleria flowleri is the only protist of it's genus to be able to enter the human body. A majority of infections occur when the amoeba enters the body through water in the nasal passage. Although the specifics are still unknown, studies have shown that Naegleria floweri is able to overcome the nasal mucosa through mucus degradation via proteases, thus allowing it to reach the brain. Once in the brain, the amoeba is able to internalize surface-bound antibodies, allowing it to avoid immune cells.

Sources: (5)

Sources: (7), (4 - image)

References:

1. Illness and symptoms. https://www.cdc.gov/parasites/naegleria/illness.html (accessed Apr 7, 2023).
2. CDC - dpdx - free living Amebic infections. https://www.cdc.gov/dpdx/freelivingamebic/index.html#:~:text=Naegleria%20fowleri%20trophozoites.&text=The%20ameboid%20trophozoites%20measure%2010,karyosome%20and%20lacks%20peripheral%20chromatin. (accessed Apr 7, 2023).
3. Piñero, J. E.; Chávez-Munguía, B.; Omaña-Molina, M.; Lorenzo-Morales, J. Naegleria Fowleri. https://www.cell.com/trends/parasitology/fulltext/S1471-4922%2819%2930162-X#secst0005 (accessed Apr 7, 2023).
4. Pervin, N. In StatPearls; Sundareshan, V., Ed.; StatPearls Publishing: Treasure Island, Florida, 2023.
5. Integrated Taxonomic Information System - Report. https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=43896#null (accessed Apr 7, 2023).
6. Martinez, A. J. In Medical Microbiology; S, B., Ed.; University of Texas Medical Branch at Galveston: Galveston, Texas, 1996.
7. Author links open overlay panelRuqaiyyah Siddiqui a; a; b; AbstractNaegleria fowleri is a protist pathogen that can cause lethal brain infection. Despite decades of research; González-Robles, A.; Ginger, M. L.; Fulton, C.; Fritz-Laylin, L. K.; Ferrante, A.; Eisen, D.; Jonckheere, J. F. D.; Cleary, S. F.; Chu, D. M.; Chávez-Munguía, B.; Cetin, N.; Carrasco-Yepez, M.; Byers, T. J.; Barbour, S. E.; Barbeau, J.; Baig, A. M.; Anderson, K.; Aldape, K.; Ahmad, A. F.; Abraham, S. N.; Adl, S. M.; Ahn, M. H.; Anon; Antonios, S. N.; Averner, M.; Baverstock, P. R.; Behets, J.; Bose, K.; Brinkley, C.; Budge, P. J.; Buse, H. Y.; Bush, L. E.; Cain, A. R.; Capewell, L. G.; Cariou, M. L.; Carter, R. F.; Casson, N.; Cerva, L.; Cervantes-Sandoval, I. Biology and pathogenesis of Naegleria Fowleri. https://www.sciencedirect.com/science/article/pii/S0001706X16305897?via=ihub (accessed Apr 7, 2023).