C. perfringens: Difference between revisions

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==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?
<i>Clostridium perfringens</i> has a single circular chromosome made up of approximately 3,031,430 base pairs with a guanine-cytosine (GC) count of about 28.6%. This is a relatively low GC content compared to that of other Gram-positive bacteria. <br>
 
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The genome contains typical anaerobic fermentation enzymes that lead to gas production; however, no enzymes for the tricarboxylic acid cycle or respiratory chain are present. Twenty genes were newly identified as virulence factors of <i>C. perfringens</i>. Also, a total of five hyaluronidase genes that contribute to virulence were recently discovered.<br>
<br>
<i>C. perfringens</i> obtains various essential materials from the host by producing several degradative enzymes and toxins, resulting in massive destruction of the host tissues.


==Cell Structure, Metabolism and Life Cycle==
==Cell Structure, Metabolism and Life Cycle==

Revision as of 05:16, 15 April 2011

This student page has not been curated.

Classification


Genus: Clostridium
Species: Perfringens
Domain: Bacteria
Phylum: Firmicutes
Order: Clostridiales
Class: Clostridia

Species

NCBI: Taxonomy

Genus species

Description and Significance

In the 1890s, Clostridium perfringens was known as Clostridium welchii. F.W. Andrewes and E. Klein linked C. perfringens to many food-born outbreaks at the time. C. perfringens is a gram-positive, anaerobic, spore-forming bacterium. Furthermore, it is a non-motile, mesophillic, encapsulated rod with square ends shaped microorganism.

C. perfringens is found virtually everywhere in nature, except in the sand of the Sahara desert, because it is spore-forming. It is common in soil, but has also been found in decaying vegetation, in the intestinal tract of humans and animals, in insects, and in marine sediment.

C. perfringens produces acetone, butanol, ethanol, butyric acid, acetic acid, propionic acid, lactic acid, carbon dioxide and hydrogen. In addition, it ferments sugars, starch and pectin. C. perfringens is the most common cause of clostridial gas gangrene; it has been known to cause 80-90% of human cases. C. perfringens is an excellent model for genetic studies of the clostridium genus due to its oxygen tolerance and fast growth rate.

Genome Structure

Clostridium perfringens has a single circular chromosome made up of approximately 3,031,430 base pairs with a guanine-cytosine (GC) count of about 28.6%. This is a relatively low GC content compared to that of other Gram-positive bacteria.

The genome contains typical anaerobic fermentation enzymes that lead to gas production; however, no enzymes for the tricarboxylic acid cycle or respiratory chain are present. Twenty genes were newly identified as virulence factors of C. perfringens. Also, a total of five hyaluronidase genes that contribute to virulence were recently discovered.

C. perfringens obtains various essential materials from the host by producing several degradative enzymes and toxins, resulting in massive destruction of the host tissues.

Cell Structure, Metabolism and Life Cycle

Interesting features of cell structure; how it gains energy; what important molecules it produces.


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.

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.

Author

Page authored by _____, student of Prof. Doreen Cunningham at Saint Augustine's College.