Ruminococcus

A Microbial Biorealm page on the genus Ruminococcus

Ruminococcus albus. Photo by Mark Morrison.

Classification

Higher order taxa:

Bacteria; Firmicutes; Clostridia; Clostridiales; Lachnospiraceae

Species:

Ruminococcus albus, R. bromii, R. flavefaciens

NCBI: Taxonomy Genome

Description and Significance

Ruminococcus is Gram-positive bacteria.

Genome Structure

Work has been started on the Ruminococcus genome structure. In 1995, the genome of Ruminococcus flavefaciens plasmid pBAW301 was sequenced. In 2004, Rincón et. al. discovered a new gene, scaC, in R. flavefaciens. This gene is part of a cluster that codes for ScaA and ScaB, which are components of the cellulosome.

Cell Structure and Metabolism

Light micrograph of Ruminococcus luti. Simmering et. al., "Ruminococcus luti sp. nov., Isolated from a Human Faecal Sample."

Ruminococcus are non-motile organisms with a coccoid shape.

Ruminococcus are anaerobic bacteria. They obtain nutrients by breaking down cellulose that comes through the digestive system of the host organism. These organisms are also capable of fermenting glucose and xylose.

Ruminococcus do not produce spores.

Ecology

Ruminococcus inhabits the rumen of cattle, sheep, and goats. These organisms allow their hosts to digest cellulose. Ruminococcus' cellulose degredation abilities are currently a major area of study. By understanding how these organisms degrade cellulose, farmers may be able to make advances in animal productivity. In addition, this knowledge could have an environmental impact. It has been suggested that scientists could develop better methods of recycling paper and wood materials.

Simmering et. al. (2002) proposed a new species, Ruminococcus luti, found not in the rumen of cattle, but in human feces. These bacteria are found in chains of up to ten cells. It does not appear to be pathogenic. Cellulolytic Ruminococcus spp. are also detected in many gut habitats including the rumen of goat, sheep and cows and the hindgut of horses, pigs and wild mammals as well as in the human large intestine.

References

Devillard, Estelle, Dara B. Goodheart, Sanjay K. R. Karnati, Edward A. Bayer, Raphael Lamed, Joshua Miron, Karen E. Nelson, and Mark Morrison. "Ruminococcus albus 8 Mutants Defective in Cellulose Degradation Are Deficient in Two Processive Endocellulases, Cel48A and Cel9B, Both of Which Possess a Novel Modular Architecture." J Bacteriol. 2004 January; 186(1): 136–145.

Genome News Network. "Gut reactions: Sequencing ruminal bacteria." 26 April 2002. Accessed 20 July 2005.

Reveneau, Carine, Sarah. E. Adams, M.A. Cotta, and M. Morrison. "Phenylacetic and Phenylpropionic Acids Do Not Affect Xylan Degradation by Ruminococcus albus." Appl Environ Microbiol. 2003 November; 69(11): 6954–6958.

Rincón, Marco T., Jennifer C. Martin, Vincenzo Aurilia, Sheila I. McCrae, Garry J. Rucklidge, Martin D. Reid, Edward A. Bayer, Raphael Lamed, and Harry J. Flint. "ScaC, an Adaptor Protein Carrying a Novel Cohesin That Expands the Dockerin-Binding Repertoire of the Ruminococcus flavefaciens 17 Cellulosome." J Bacteriol. 2004 May; 186(9): 2576–2585.

Simmering, Rainer, David Taras, Andreas Schwiertz, Gwenaelle Le Blay, Bärbel Gruhl, Paul A. Lawson, Matthew D. Collins, and Michale Blaut. "Ruminococcus luti sp. nov., Isolated from a Human Faecal Sample." Systematic and Applied Microbiology. 2002;25:189-193.