''Fusobacterium'' is a genus of

anaerobic Anaerobic means "living, active, occurring, or existing in the absence of free oxygen", as opposed to aerobic which means "living, active, or occurring only in the presence of oxygen." Anaerobic may also refer to: *Adhesive#Anaerobic, Anaerobic ad ...

Gram-negative Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wa ...

, non-sporeforming bacteria belonging to Gracilicutes. Individual cells are slender, rod-shaped

bacilli Bacilli is a taxonomic class of bacteria that includes two orders, Bacillales and Lactobacillales, which contain several well-known pathogens such as ''Bacillus anthracis'' (the cause of anthrax). ''Bacilli'' are almost exclusively gram-posit ...

with pointed ends. Strains of ''Fusobacterium'' cause several human diseases, including

periodontal disease Periodontal disease, also known as gum disease, is a set of inflammatory conditions affecting the tissues surrounding the teeth. In its early stage, called gingivitis, the gums become swollen and red and may bleed. It is considered the main cau ...

Lemierre's syndrome Lemierre's syndrome is infectious thrombophlebitis of the internal jugular vein. It most often develops as a complication of a bacterial sore throat infection in young, otherwise healthy adults. The thrombophlebitis is a serious condition and ma ...

, and topical

skin ulcers An ulcer is a sore on the skin or a mucous membrane, accompanied by the disintegration of tissue. Ulcers can result in complete loss of the epidermis and often portions of the dermis and even subcutaneous fat. Ulcers are most common on the skin ...

. Although older sources state that ''Fusobacterium'' is part of the normal flora of the human

oropharynx The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its struc ...

, the current consensus is that ''Fusobacterium'' should always be treated as a pathogen. ''F. prausnitzii'', a gut commensal associated with healthy patients, was completely reclassified as '' Faecalibacterium'' (''Clostridiales'':''Ruminococcaceae'') in 2002.

Clinical relevance

''Fusobacterium'' is often associated with

ulcerative colitis Ulcerative colitis (UC) is a long-term condition that results in inflammation and ulcers of the colon and rectum. The primary symptoms of active disease are abdominal pain and diarrhea mixed with blood ( hematochezia). Weight loss, fever, an ...

. Research of

colon cancer Colorectal cancer (CRC), also known as bowel cancer, colon cancer, or rectal cancer, is the development of cancer from the colon or rectum (parts of the large intestine). Signs and symptoms may include blood in the stool, a change in bowel ...

has also shown an overrepresentation of ''Fusobacterium'', both in feces of patients and tumor issue itself. Whether ''Fusobacterium'' causes these diseases or only colonizes existing tumours, remains undetermined. The bacterium is a big anchor for biofilms. It is usually susceptible to

clindamycin Clindamycin is an antibiotic medication used for the treatment of a number of bacterial infections, including osteomyelitis (bone) or joint infections, pelvic inflammatory disease, strep throat, pneumonia, acute otitis media (middle ear infe ...

, while approximately 20% of the clinical strains are resistant to

penicillin Penicillins (P, PCN or PEN) are a group of β-lactam antibiotics originally obtained from ''Penicillium'' moulds, principally '' P. chrysogenum'' and '' P. rubens''. Most penicillins in clinical use are synthesised by P. chrysogenum using ...

. In contrast to '' Bacteroides'' spp., ''Fusobacterium'' has a potent

lipopolysaccharide Lipopolysaccharides (LPS) are large molecules consisting of a lipid and a polysaccharide that are bacterial toxins. They are composed of an O-antigen, an outer core, and an inner core all joined by a covalent bond, and are found in the outer ...

Phylogeny

References

External links

''Anaerobic Gram-Negative Bacilli'' chapter
in Baron's ''Medical Microbiology'' (online at the NCBIbr>bookshelf
.
''Fusobacterium''
From MicrobeWiki, the student-edited microbiology resource {{Taxonbar, from=Q2720082 Gut flora bacteria Fusobacteriota Bacteria genera

Clinical relevance

Phylogeny

See also

References

External links