Ralstonia solanacearum: Difference between revisions

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==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.
Describe any interesting features and/or cell structures; how it gains energy; what important molecules it produces.
<i>Ralstonia solanacearum</i> is a Gram negative pathogen.  It has an outer membrane and inner membrane.  Its cell walls consist of peptidoglycan.(6) 
The plant pathogen Ralstonia solanacearum needs aerotaxis for normal biofilm formation.  In order to locate and infect host plant roots, R. solanacearum needs taxis, the ability to move towards more favorable conditions. Aerotaxis, or energy taxis, which guides bacteria toward optimal intracellular energy levels. The energy taxis contributes significantly to the ability of R. solanacearum to locate and effectively interact with its host plants.(7)
It is known to produce a potent L-fuctose-binding lectin, RSL, a small protein of 90 amino acids with a tandem repeat in its amino acid sequence.  The RSL forms a trimer which produces a six-bladed Beta-propellor.  Host plant cell walls contain carbohydrates which enable attachment sites for the pathogen protein receptors.  In this case, the lectin has a great affinity for αFuc1-2Gal and αFuc1-6Gal epitopes found on certain plants. (6)


==Ecology==
==Ecology==

Revision as of 21:54, 20 August 2007

A Microbial Biorealm page on the genus Ralstonia solanacearum

Classification

Higher order taxa

Bacteria; Proteobacteria; Beta Proteobacteria; Burkholderiales; Ralstoniaceae [Others may be used. Use NCBI link to find]

Species

NCBI: Taxonomy

Ralstonia solanacearum

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. Include a picture or two (with sources) if you can find them.

<a href="http://photobucket.com" target="_blank"><img src="http://i8.photobucket.com/albums/a40/dangitscam2/Ralstonia.jpg" border="0" alt="Photo Sharing and Video Hosting at Photobucket"></a> (3)

Ralstonia solanacearum is a plant pathogenic bacterium. This organism causes bacterial wilts and infection of over 200 plants species. It is usually found in soils of tropical and subtropical countries. This pathogen can lie dormant in water or soil until a host plant grows. Once the host begins to develop, the organism spreads throughout the plant by entering the roots and colonizing water-conducting vessels.(1)

Through genome sequencing, we observe that the genome encodes many proteins potentially associated with a role in pathogenicity. In particular, many putative attachment factors were identified. (2) The analysis of the genome has made it possible to identify more than 200 new genes that are potentially involved in virulence. (4)

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? Does it have any plasmids? Are they important to the organism's lifestyle?


R. solanacearum genome into two circular molecules: a large replicon of 3,716,413 bp and a smaller 2,094,509-bp replicon, yielding a total genome size of 5,810,922 bp. The two molecules have an almost identical G+C content (67.04% and 66.86% for the large and small replicon, respectively).(5) The genome encodes many proteins potentially associated with a role in pathogenicity.

Cell structure and metabolism

Describe any interesting features and/or cell structures; how it gains energy; what important molecules it produces.

Ralstonia solanacearum is a Gram negative pathogen. It has an outer membrane and inner membrane. Its cell walls consist of peptidoglycan.(6)

The plant pathogen Ralstonia solanacearum needs aerotaxis for normal biofilm formation. In order to locate and infect host plant roots, R. solanacearum needs taxis, the ability to move towards more favorable conditions. Aerotaxis, or energy taxis, which guides bacteria toward optimal intracellular energy levels. The energy taxis contributes significantly to the ability of R. solanacearum to locate and effectively interact with its host plants.(7)


It is known to produce a potent L-fuctose-binding lectin, RSL, a small protein of 90 amino acids with a tandem repeat in its amino acid sequence. The RSL forms a trimer which produces a six-bladed Beta-propellor. Host plant cell walls contain carbohydrates which enable attachment sites for the pathogen protein receptors. In this case, the lectin has a great affinity for αFuc1-2Gal and αFuc1-6Gal epitopes found on certain plants. (6)

Ecology

Describe any interactions with other organisms (included eukaryotes), contributions to the environment, effect on environment, etc.

Pathology

How does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms.

Application to Biotechnology

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

Current Research

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

References

[Sample reference] Takai, K., Sugai, A., Itoh, T., and Horikoshi, K. "Palaeococcus ferrophilus gen. nov., sp. nov., a barophilic, hyperthermophilic archaeon from a deep-sea hydrothermal vent chimney". International Journal of Systematic and Evolutionary Microbiology. 2000. Volume 50. p. 489-500.

Edited by student of Rachel Larsen