Plasmodium malariae
A Microbial Biorealm page on the genus Plasmodium malariae
<a href="http://phil.cdc.gov/phil/details.asp" class="image"><img alt="" src="http://phil.cdc.gov/PHIL_Images/12563/12563_lores.jpg" width="240" height="162" /></a>
Classification
Higher order taxa
Domain: Eukarya
Phylum: Apicomplexa
Class: Aconoidasida
Order: Haemosporida
Family: Plasmodiidae
(NCBI)
Species
Plasmodium malariae
Description and significance
Describe the appearance, habitat, etc. of the organism, and why you think it is important.
-Plasmodium malariae is a parasitic protozoa that causes malaria in humans. It is the cause of a fever that recurs in three-day intervals and is responsible for less death than malaria caused by other bacteria.
Genome structure
Describe the size and content of the genome. How many chromosomes? Circular or linear? Other interesting features? What is known about its sequence?
Not much is known about the genome of the species Plasmodium malariae specifically, but some important characteristics about its genome can be determined from the genome sequences of other species in the Plasmodium genus. It is estimated that the genome of an organism in the genus Plasmodium contains anywhere from 23 million to 27 million base pairs, in the form of 14 linear chromosomes. These 14 chromosomes code for about 5,500 genes, many of which function in invading the host immune system. (Winzeler)
Cell structure and metabolism
Interesting features of cell structure; how it gains energy; what important molecules it produces.
Ecology
Habitat; symbiosis; contributions to the environment.
Pathology
P. malariae is one of the four species of the genus Plasmodium that uses humans as a primary host. The other three species are P. falciparum, P. vivax,and P. vivale. The primary mode of transmission from host to host by these four species uses a female Anopheles mosquito as a vector. (DPDx) While the symptoms resulting from the different species are different, the life cycle only has minor differences. The life cycle is initiated when the mosquito vector injects sporozites into the human hosts during a blood-meal. The sporozites then migrate to the liver, where they reproduce asexually and produce merozites. These merozites then enter the bloodstream and infect erythrocytes, becoming trophozoites. The period of time that the trophozoites are enlarging is called the trophic period, and this ends when several divisions occur, but none of these cycles go through the cytokinesis stage, forming what is called a schizont. The erythrocyte then lyses, introducing new merozites into the blood cycle and starting the cycle over again, until an uninfected Anopheles mosquito takes a blood-meal from the infected host, and transmits the infection to another host. (Wiser)
The main physical manifestations of malaria in a human host are febrile attacks that are known as malarial paroxysms. These symptoms appear during the blood stage of the life cycle; no symptoms will appear during other stages. The severity of the infection depends on the infecting species of Plasmodium and the health of the host prior to infection. (Wiser)
Current Research
Enter summaries of the most recent research here--at least three required
Researchers at the National Institute of Allergy and Infectious Diseases are using genetic studies of Plasmodium yoelii, isolated from wild African rodents to understand pathogenicity of malaria parasites. P. yoelii exhibits traits similar to human malaria viruses such as Plasmodium falciparum and Plasmodium malariae. The article is a methods video and article describing how to obtain a genetic cross of rodent malaria parasites. Published in January of 2011, http://www.jove.com/details.php?id=2365 .
Cool Factor
Describe something you find "cool" about this microbe.
References
-DPDx - Parasitology Diagnostic Web Site. "Parasites and Health - Malaria." Laboratory Identification of Parasites of Public Health Concern. Center for Disease Control (CDC), 20 July 2009. Web. 07 Oct. 2011. <http://dpd.cdc.gov/dpdx/html/Malaria.htm>.
-Pattaradilokrat, S., Li, J., Su, X. . Protocol for Production of a Genetic Cross of the Rodent Malaria Parasites. J. Vis. Exp. (47), e2365, DOI: 10.3791/2365 (2011) http://www.jove.com/details.php?id=2365.
-"Plasmodium Malariae." NCBI Taxonomy Browser. NCBI. Web. 05 Oct. 2011. <http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi>.
-Winzeler, Elizabeth Ann. "Malaria research in the post-genomic era." Nature 455.7214 (2008): 751-756. Academic Search Premier. EBSCO. Print. 5 Oct. 2011.
-Wiser, Mark F. "Plasmodium Life Cycle." Tulane University. Web. 7 Oct. 2011. <http://www.tulane.edu/~wiser/malaria/mal_lc.PDF>.
Edited by students of Iris Keren
NEUF2011
