Plasmodium knowlesi: Difference between revisions
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==Genome structure== | ==Genome structure== | ||
: There are currently 5 strains of Plasmodium knowlesi that have been archived. P. knowlesi has 14 chromosomes on which a total of 5,102 protein-encoding genes have been identified. Unlike other Plosmodium species, (G+C) - rich repeat regions containing intrachromosomal telomeric sequences (ITSs, containing the sequence GGGTT[T/C]A) are found at multiple sites in P. knowlesi chromosomes. These sequences may be templates for the recombinations that result in gene conversion among variant antigen genes. ITSs are also thought to play a role in transcriptional control. Another unique feature of P. knowlesi is that it contains five distinct gene families with 4–15 paralogous members of unknown function. P. knowlesi does not have any plasmids. | |||
: Acquisition of host proteins, and thus the ability to mimic their function, has been observed in many bacterial and viral pathogens. Malaria parasites, such as P. knowlesi, are known to have a potential immunomodulatory role either by secreting functional homologues of host molecules or by binding to host antigen-presenting cells. P. knowlesi is the first strain observed in which a malaria protein has acquired host peptide sequences that are likely to be on the infected cell surface and thus may interact with the host. The mechanism by which the virus acquires these host sequences has yet to be discovered. | |||
==Cell structure, metabolism & life cycle== | ==Cell structure, metabolism & life cycle== | ||
Revision as of 17:18, 31 October 2011
A Microbial Biorealm page on the genus Plasmodium knowlesi
Classification
- Eukaryota, Alveolata, Apicomplexa, Aconoidasida, Haemosporida, Plasmodium, knowlesi
Description and significance
- Plasmodium knowlesi is one of 5 known strains of malaria and is the most recently discovered strain of the group. Initially discovered in 1927 by Giuseppe, the parasite originally caused malaria in long-tailed and pig-tailed macaques. However, more recently P. knowlesi has been a popular source of malaria in humans due to urban development and increased interactions with forest fringes. In certain areas of South East Asia it accounts for up to 70% of all malaria cases. The virus can be transmitted to humans both directly, by the bite of an infected macaques, or indirectly through the bite of a mosquito carrying the virus. Plasmodium knowlesi has health, social and economic consequences for the regions affected by it. Although treatable, malaria continues to be the most important cause of fever and morbidity in tropical regions of the world. The virus undergoes asexual erythrocytic cycle replication in a 24 hour time period and therefore is known to cause sever and rapid cases of malaria in humans upon infection.
Genome structure
- There are currently 5 strains of Plasmodium knowlesi that have been archived. P. knowlesi has 14 chromosomes on which a total of 5,102 protein-encoding genes have been identified. Unlike other Plosmodium species, (G+C) - rich repeat regions containing intrachromosomal telomeric sequences (ITSs, containing the sequence GGGTT[T/C]A) are found at multiple sites in P. knowlesi chromosomes. These sequences may be templates for the recombinations that result in gene conversion among variant antigen genes. ITSs are also thought to play a role in transcriptional control. Another unique feature of P. knowlesi is that it contains five distinct gene families with 4–15 paralogous members of unknown function. P. knowlesi does not have any plasmids.
- Acquisition of host proteins, and thus the ability to mimic their function, has been observed in many bacterial and viral pathogens. Malaria parasites, such as P. knowlesi, are known to have a potential immunomodulatory role either by secreting functional homologues of host molecules or by binding to host antigen-presenting cells. P. knowlesi is the first strain observed in which a malaria protein has acquired host peptide sequences that are likely to be on the infected cell surface and thus may interact with the host. The mechanism by which the virus acquires these host sequences has yet to be discovered.
Cell structure, metabolism & life cycle
Provide a physical and biochemical description of the organism. What kind of organism is it, what does it look like, how is it built, what are its metabolic properties, how can it be identified, what is it's life cycle, &c. In other words, describe the organism from its perspective.
Ecology (including pathogenesis)
Describe its habitat, symbiosis, and contributions to environment. If it is a pathogen, how does this organism cause disease? Human, animal, plant hosts? Describe virulence factors and patient symptoms.
Interesting feature
Describe in detail one particularly interesting aspect of your organism or it's affect on humans or the environment.
