Lawsonia intracellularis: Difference between revisions

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'''NCBI: [http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Tree&id=2&lvl=3&lin=f&keep=1&srchmode=1&unlock Taxonomy]'''
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Edited by Neena Patel, student of Rachel Larsen at UCSD.


==Description and significance==
==Description and significance==
Describe the appearance, habitat, etc. of the organism, and why it is important enough to have its genome sequenced.  Describe how and where it was isolated.
Lawsonia Intracellularis is a bacterial pathogen which causes disease in a wide range of animals, mainly pigs. The bacterial pathogen invades the intestinal epithelial cells which causes hyperplasia of the infected cells which leads to the process of disease pathogenesis. Lawsonia intracelluaris is an intracellular enterophathogen that is the cause of intestinal hyperplasia which include proliferative enteropathy, intestinal adenomatosis, and ileitis. Lawsonia intracellularis though primarily recognized in pigs, is spreading to a wide range of mammals. With a 16SrRNA gene sequence, Lawsonia intracellularis is related to Desulfovibio, a sulfate-reducing bacteria and Bilophila wadsworthia.
Include a picture or two (with sources) if you can find them.
 
''Treponema denticola'' is a motile, slender, helically shaped flexible organism. It is made up of a periplasmic flagella wound around the helical protoplasmic cylinder and encased in an outer sheath. It's habitat is anaerobic and host-associated. It grows at an optimal temperature of 30-42°C, with a pH of 6.5-8.0. It is commonly found in the human oral cavity, specifically in subgingival dental plaque, and it is often associated with periodontal disease. Periodontal disease results in inflammation of the gum tissue, bone resorbtion, and subsequent tooth loss. Periodontal disease has now become a major concern in dentistry and 80% of adults in the USA are estimated to have had periodontal disease at some point in their lives.
The complete genome of T. denticola strain 35405 was sequenced by using the random shotgun method described for genomes sequenced by The Institute for Genomic Research and it was designated as the type strain by Chan et al.
 


Edited by Neena Patel, student of Rachel Larsen at UCSD.


==Genome structure==
==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?
Lawsonia intracellularis is made up of a circular chromosome and the length is 1,457,619 nucleotides. The genomic content includes 1,719,014 nucleotides. It had 1, 337 protein genes and 49 RNA genes.
Does it have any plasmids?  Are they important to the organism's lifestyle?


Treponema denticola ATCC 35405 has a complete genome. It is made up of dsDNA and 1 chromosome. It is circular and the length is 2,843,201 nucleotides. The GC content is 37%. It has 2838 genes.
Replicon Type: chromosome.
Edited by Neena Patel, student of Rachel Larsen at UCSD.


==Cell structure and metabolism==
==Cell structure and metabolism==
Describe any interesting features and/or cell structures; how it gains energy; what important molecules it produces.
The structure of Lawsonia intracellularis reveals non-spore-forming curved rods. It contains gram-negative cells that are able to retain carbol-fushsin when stained using the Ziehl-Neelsen method. It is nonpifmented and nonflagellated. Through the Ziehl-Neelsen method the cell wall of a gram-negative is shown as well as the protoplasmic structure of a prokaryote. The cells replicate within the cytplasm and are not enclosed by membrane-bound vacuoles. This occurs in epitheilial cells of pigs.


The genome reveals factors mediating coaggregation, cell signaling, and stress protection. It has a spiral shape and is arranged in singles. It is a mobile organism but does not contain any endospores. Motility is by rapid rotation around the long axis, flexation of the cell and locomotion along a helical path. The most distinctive property is the presence of periplasmic flagella wound around the helical protoplasmic cylinder and encased in an outer sheath.
Edited by Neena Patel, student of Rachel Larsen at UCSD.


==Ecology==
==Ecology==
Describe any interactions with other organisms (included eukaryotes), contributions to the environment, effect on environment, etc.
Natural infection has not been detected in either wild or laboratory mice however, the former represent a potential reservoir; hence, our findings have further implications for the ecology and epidemiology of PE, particularly in pigs, where the environment is likely to be cohabited by rodents.
Although pigs have been considered the major susceptible animal, it is becoming increasingly apparent that L. intracellularis has a broad host range which is potentially wider than currently known. Despite evidence of infection in primates, there is currently no direct evidence that L. intracellularis can infect humans, although one report has suggested a link with human disease. In view of the known broad host range of L. intracellularis and the wide spectrum in clinical presentation we should remain alert to the possibility that the range of susceptible species may broaden further and may incorporate humans.


==Pathology==
==Pathology==
''Treponema denticola'' is a bacterial pathogen and plant plastid. It causes periodontal disease and gum inflammation.
Lawsonia intracellularis is an intracellular bacterial pathogen which cause intestinal hyperplasia in a wide range of mammalian and avian species.


How does this organism cause disease?  Human, animal, plant hosts?  Virulence factors, as well as patient symptoms.
Edited by Neena Patel, student of Rachel Larsen at UCSD.


==Application to Biotechnology==
==Application to Biotechnology==
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==Current Research==
==Current Research==


Enter summaries of the most recent research here--at least three required
 


==References==
==References==
example:
[http://www.pnas.org/cgi/content/full/100/14/8298 Glockner, F. O., M. Kube, M. Bauer, H. Teeling, T. Lombardot, W. Ludwig, D. Gade, A. Beck, K Borzym, K Heitmann, R. Rabus, H. Schlesner, R. Amann, and R. Reinhardt. 2003. "Complete genome sequence of the marine planctomycete ''Pirellula'' sp. strain 1."'' Proceedings of the National Acedemy of Sciences'', vol. 100, no. 14. (8298-8303)]
Edited by student of [mailto:ralarsen@ucsd.edu Rachel Larsen] and Kit Pogliano

Revision as of 06:51, 3 May 2007

Template:Biorealm genus

Classification

Gram-negative

Higher order taxa

Phylum: Bacteria

Bacteria; Proteobacteria; Deltaproteobacteria; Desulfovibrionales; Desulfovibrionaceae; Lawsonia.

Strain: PHE/MN1-00.

(there may be additional subcategories included as well. You can just copy this information from the NCBI taxonomy page)


Genus

Genus species: Lawsonia intracellularis



Description and significance

Lawsonia Intracellularis is a bacterial pathogen which causes disease in a wide range of animals, mainly pigs. The bacterial pathogen invades the intestinal epithelial cells which causes hyperplasia of the infected cells which leads to the process of disease pathogenesis. Lawsonia intracelluaris is an intracellular enterophathogen that is the cause of intestinal hyperplasia which include proliferative enteropathy, intestinal adenomatosis, and ileitis. Lawsonia intracellularis though primarily recognized in pigs, is spreading to a wide range of mammals. With a 16SrRNA gene sequence, Lawsonia intracellularis is related to Desulfovibio, a sulfate-reducing bacteria and Bilophila wadsworthia.


Genome structure

Lawsonia intracellularis is made up of a circular chromosome and the length is 1,457,619 nucleotides. The genomic content includes 1,719,014 nucleotides. It had 1, 337 protein genes and 49 RNA genes.


Cell structure and metabolism

The structure of Lawsonia intracellularis reveals non-spore-forming curved rods. It contains gram-negative cells that are able to retain carbol-fushsin when stained using the Ziehl-Neelsen method. It is nonpifmented and nonflagellated. Through the Ziehl-Neelsen method the cell wall of a gram-negative is shown as well as the protoplasmic structure of a prokaryote. The cells replicate within the cytplasm and are not enclosed by membrane-bound vacuoles. This occurs in epitheilial cells of pigs.


Ecology

Natural infection has not been detected in either wild or laboratory mice however, the former represent a potential reservoir; hence, our findings have further implications for the ecology and epidemiology of PE, particularly in pigs, where the environment is likely to be cohabited by rodents. Although pigs have been considered the major susceptible animal, it is becoming increasingly apparent that L. intracellularis has a broad host range which is potentially wider than currently known. Despite evidence of infection in primates, there is currently no direct evidence that L. intracellularis can infect humans, although one report has suggested a link with human disease. In view of the known broad host range of L. intracellularis and the wide spectrum in clinical presentation we should remain alert to the possibility that the range of susceptible species may broaden further and may incorporate humans.


Pathology

Lawsonia intracellularis is an intracellular bacterial pathogen which cause intestinal hyperplasia in a wide range of mammalian and avian species.


Application to Biotechnology

Does this organism produce any useful compounds or enzymes? What are they and how are they used?

Current Research

References