Oxalobacter formigenes: Difference between revisions
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Interesting features of cell structure; how it gains energy; what important molecules it produces. | Interesting features of cell structure; how it gains energy; what important molecules it produces. | ||
Figure 1: Oxalate metabolism by Oxalobacter formigenes [Stewart] | |||
[[Image:Oxalate degradation.jpg]] | [[Image:Oxalate degradation.jpg]] | ||
Revision as of 00:50, 14 April 2009
Classification
Bacteria; Proteobacteria; Betaproteobacteria; Burkholderiales; Oxalobacteraceae; Oxalobacter
Species
Oxalobacter Formigenes
Description and Significance
Describe the appearance, habitat, etc. of the organism, and why you think it is important.
Oxalobacter formigenes is a gram negative beta-proteobacterium that colonizes the human large intestine (colon) [stewart]. O. formigenes is a strict anaerobe and is thought to be largely important in the metabolism of dietary oxalate [stewart]. The absence of O. formigenes is thought to be a cause of hyperoxaluria and the formation of calcium oxalate stones in the kidney [Siva], and it is thought that O. formigenes may be useful as a probiotic agent for the treatment of these conditions [stewart].
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?
Two separate shotgun sequencing projects are currently under way to sequence the genome of O. formigenes, Neither of these projects are complete (and they each have many unresolved contigs). The length of genetic material currently sequenced is approximately 2.4 MB for both projects, and the GC content of this sequence approximately 50%. The currently available sequence likely does not encompass the entire genome due to toxic or unstable (unable to be cloned) portions of the genome. The genome has not yet been annotated, and the number of chromosomes and characteristics of the genome (such as circularity or linearity) are unknown.
Cell Structure, Metabolism and Life Cycle
Interesting features of cell structure; how it gains energy; what important molecules it produces.
Figure 1: Oxalate metabolism by Oxalobacter formigenes [Stewart]
Ecology and Pathogenesis
Habitat; symbiosis; biogeochemical significance; contributions to environment.
If relevant, how does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms.
The habitat of this organism is the large intestine of the human gut, and although it is not initially found in the gut at birth, O. formigenes quickly is established in the gut microflora [Mittal]. O. formigenes plays a unique role in the gut microflora in that it is capable of metabolizing 70 to 100 mg per day of oxalate that is ingested in one’s diet [Mittal]. Although soluble oxalate is absorbed in the human small intestine, O. formigenes fulfills the role of metabolizing the remaining dietary oxalate, which can accumulate, leading to hyperoxaluria and the formation of calcium oxalate stones, which are harmful to the human host [Siva]. This can be considered a symbiosis, in that the organism, a strict anaerobe, is given a safe environment to live and reproduce, along with a steady supply of oxalate to consume. In addition, O. formigenes confers a benefit to its human host. O. formigenes is not explicitly pathogenic.
References
Author
Page authored by Mark Charbonneau and Ashley Behan, students of Prof. Jay Lennon at Michigan State University.
