''Flavonifractor plautii'' is a bacterium of the

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

genus '' Flavonifractor'' in the family ''

Oscillospiraceae Oscillospiraceae, also commonly called Ruminococcaceae, is a family of bacteria in the class Clostridia. All Oscillospiraceae are obligate anaerobes. However, members of the family have diverse shapes, with some rod-shaped and others cocci. With ...

''.

History

This species was originally placed in the genus ''Fusobacterium'' by S. Seguin in 1928, and was later recategorized as ''Fusocillus'' in 1938 by A.R. Prevot. This classification remained until 1962, when M. Sebald renamed the species ''Zuberella plauti''. In 1928, Skerman VBD and colleagues referred to this species as ''Fusobacterium plauti'' in the “Approved Lists of Bacterial Names”. In 1982, Hofstad and Aasjord officially assigned the name ''Eubacterium plautii'' to this species. In 1991, Winter et al. highlighted the bacterium’s ability to cleave flavonoids and introduced its basionym as ''Clostridium orbiscindens''. Finally, in 2010, Carlier et al. proposed the unification of ''Clostridium orbiscindens'' and ''Eubacterium plautii'' under the new name ''Flavonifractor plautii''. The cells are described as straight or slightly curved rods, 2–10 microns long, occurring singly or in pairs. Strains have been isolated from human feces, blood, intra-abdominal pus, and infected soft tissues.

Genome

''Flavonifractor plautii'' has a genome consisting of a single circular

chromosome A chromosome is a package of DNA containing part or all of the genetic material of an organism. In most chromosomes, the very long thin DNA fibers are coated with nucleosome-forming packaging proteins; in eukaryotic cells, the most import ...

with 3,985,392 base pairs, with a

G+C content G, or g, is the seventh letter of the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages, and others worldwide. Its name in English is ''gee'' (pronounced ), plural ''gees''. The lower ...

of 60.9%. The genome is predicted to contain 3 complete sets of

rRNA Ribosomal ribonucleic acid (rRNA) is a type of non-coding RNA which is the primary component of ribosomes, essential to all cells. rRNA is a ribozyme which carries out protein synthesis in ribosomes. Ribosomal RNA is transcribed from ribosomal ...

genes, 63

tRNA Transfer ribonucleic acid (tRNA), formerly referred to as soluble ribonucleic acid (sRNA), is an adaptor molecule composed of RNA, typically 76 to 90 nucleotides in length (in eukaryotes). In a cell, it provides the physical link between the gene ...

genes, and 3,764 protein-coding sequences.

Metabolism and ecology

This bacterium is an

obligate anaerobe Obligate anaerobes are microorganisms killed by normal Atmosphere of Earth, atmospheric concentrations of oxygen (20.95% O2). Oxygen tolerance varies between species, with some species capable of surviving in up to 8% oxygen, while others lose vi ...

that is capable of cleaving the C-ring found in

flavonoid Flavonoids (or bioflavonoids; from the Latin word ''flavus'', meaning yellow, their color in nature) are a class of polyphenolic secondary metabolites found in plants, and thus commonly consumed in the diets of humans. Chemically, flavonoids ...

s. ''Flavonifractor plautii'' is highly prevalent in the human gastrointestinal tract, and is known to be a proficient producer of

butyrate The conjugate acids are in :Carboxylic acids. {{Commons category, Carboxylate ions, Carboxylate anions Carbon compounds Anions ...

Clinical significance

''Flavonifractor plautii'' was found to be associated with

colorectal cancer Colorectal cancer (CRC), also known as bowel cancer, colon cancer, or rectal cancer, is the development of cancer from the Colon (anatomy), colon or rectum (parts of the large intestine). Signs and symptoms may include Lower gastrointestinal ...

(CRC) in a cohort of 30 CRC patients and 30 healthy controls. It was hypothesized that the degradation of beneficial anticarcinogenic flavonoids, such as quercetin, by F. plautii may contribute to the cancer. Flavonifractor plautii was also found to be significantly enriched in major depressive disorder (MDD) in a cohort of 90 American young adults (43 with MDD, 47 healthy). In pediatric

inflammatory bowel disease Inflammatory bowel disease (IBD) is a group of inflammatory conditions of the colon and small intestine, with Crohn's disease and ulcerative colitis (UC) being the principal types. Crohn's disease affects the small intestine and large intestine ...

, ''F. plautii'' was shown to preferentially bind

immunoglobulin G Immunoglobulin G (IgG) is a type of antibody. Representing approximately 75% of serum antibodies in humans, IgG is the most common type of antibody found in blood circulation. IgG molecules are created and released by plasma B cells. Each IgG ...

(IgG) from

Crohn’s disease Crohn's disease is a type of inflammatory bowel disease (IBD) that may affect any segment of the gastrointestinal tract. Symptoms often include abdominal pain, diarrhea, fever, abdominal distension, and weight loss. Complications outside of the ...

patients compared to non-

and

ulcerative colitis Ulcerative colitis (UC) is one of the two types of inflammatory bowel disease (IBD), with the other type being Crohn's disease. It is a long-term condition that results in inflammation and ulcers of the colon and rectum. The primary sympto ...

samples. It also demonstrated invasive potential ''in vitro'' using a fluorescence microscopy assay with intestinal epithelial cells in culture.

References

Bacteria described in 1928 Oscillospiraceae {{Clostridia-stub