F. succinogenes

A Microbial Biorealm page on the genus F. succinogenes

Classification (1)

Higher order taxa

cellular organisms; Bacteria; Fibrobacteres/Acidobacteria group; Fibrobacteres; Fibrobacteres (class); Fibrobacterales; Fibrobacteraceae; Fibrobacter

Species

NCBI: Taxonomy

Fibrobacter succinogenes

Description and significance

Fibrobacter succinogenes has been considered as one of the most actively fibrolytic bacteria in the rumen (Forsberg et al. 1997), as this species possesses a varity of fibrolytic enzymes (Malburg & Forsberg 1993; Bera et al. 1999) and is detected in the rumen at high density (Michalet-Doreau et al. 2001; Koike et al. 2003). All previous isolates of this species, comprising 10 strains, use limited soluble substrates such as glucose or short glucose polymer and produce similar fermentation metabolites. Meanwhile, these 10 isolates of F. succinegenes are divided into four different phylogenetic groups (Amann et al. 1992), based on comparative sequence analysis of 16S rRNA gene (16S rDNA). A few differences in phenotypic characters among these four groups have been reported: (i) group 1 is differentiated from the other groups by its pleomorphic coccoid morphology and poor ability to digest cellulose in agar medium (Montgomery et al. 1988); (ii) group 3 is distinguishable from group 2 by production of yellow pigment and requirement for vitamin B12; (iii) groups 2 and 4 cannot be distinguished by any phenotypic characters (Amann et al. 1992).

Because F. succinogenes is better characterized in phenotypic variation depending on its phylogenetic grouping (Shinkai et al. 2004), attention should now be paid to the contribution of each group to plant fiber digestion in the rumen. The contribution might be indirectly evaluated by ecological information of each group of E. succinogenes, for example, bacterial mass and localization in the rumen (3).

B18 Fibrobacteres - Gram-negative anaerobes associated with the digestive tracts of herbivores. Representative species or genus: Fibrobacter

Genome structure

As of June 2007, the genome of L. jensenii 1153 has been fully sequenced using shotgun sequencing by the Lawrence Berkeley National Lab and Osel: The Bacterio-Therapeutics Company, but the data has to be yet released to public (4). For this reason, information on native plasmids and the genome is not available. The genome was sequenced for research conducted at Stanford University, Department of Medicine, that required a better understanding of gene regulation and promoter regions so to increase efficiency of HIV inhibitor cyanovirin-N expression in Lactobacillus jensenii. (See under Current Research for more details)

Most of the sequencing methods include bacterial colony-based strain typing using PCR-fingerprinting and phylogenetic analysis of the partial 16S rRNA gene. Analysis shows that its genome contains over 1600 ORFs which include "novel cell wall anchor domains, unique signal sequences, powerful promoter elements, and possible sites for chromosomal integration of heterologous genes"(9). Its DNA has low G+C content (36.1 ± 2.3 moles % guanine + cytosine), similar to the DNA composition of L. acidophilus - L. jugurti group (36.1 ± 1.2 moles % guanine + cytosine); it produces D-lactic acid as its major metabolic product (10).

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?

Cell structure and metabolism

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

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

(1) NCBI: Fibrobacter succinogenes, Accessed Aug 22, 2007, <http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&id=833&lvl=3&lin=f&keep=1&srchmode=1&unlock>

(2) Forsberg CW, Cheng KJ, White BA. 1997. Polysaccharide degradation in the rumen and large intestine. In: Mackie RI. White BA (eds), Gastrointestinal Microbiology, pp. 319-379. Chapman and Hall, New York.

(3) Koike S, Pan J, Suzuki T, Takano T, Oshima C, Kobayashi Y, Tanaka K. 2004. Ruminal distribution of the cellulolytic bacterium Fibrobacter succinogenes in relation to its phylogenetic grouping. Animal Science Journal, 75, pp. 417-422.

Edited by Woo Cheal Cho, student of Rachel Larsen