Eikenella corrodens

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Scientific classification
Kingdom: Bacteria
Phylum: Proteobacteria
Class: Beta Proteobacteria
Order: Neisseriales
Family: Neisseriaceae
Genus: Eikenella
Species: corrodens

Eikenella corrodens is a fastidious Gram-negative facultative anaerobic bacillus. It was first identified by M. Eiken in 1958, who called it Bacteroides corrodens.[1]


E. corrodens is a pleomorphic bacillus that sometimes appears coccobacillary and typically creates a depression (or "pit") in the agar on which it is growing. Only half produce the pitting of the agar considered characteristic.

It grows in aerobic and anaerobic conditions, but requires an atmosphere enhanced by 3–10% carbon dioxide.

The colonies are small and greyish, they produce a greenish discoloration of the underlying agar, and smell faintly of bleach (hypochlorite).

They are oxidase-positive, catalase-negative, urease-negative, and indole-negative, and reduce nitrate to nitrite.

In 2006, Azakami et al reported that the periodontal pathogen E. corrodens have ortholog of luxS, the gene required for Quorum sensing (QS) signal molecule AI-2 synthesis and E. corrodens can produce AI-2 signal for cell to cell communication and AI-2 has a role on biofilm formation by E. corrodens.[5] Karim et al reported that this bacteria can produce AI-2 inactivation enzyme during its stationary phase.[6] Karim et al also reported that LuxS mediated QS may facilitate the maturation and detachment of biofilm formation in E.corrodens, which can leads to progression of periodontal disease.[7]

Medical importance[edit]

E. corrodens is a commensal of the human mouth and upper respiratory tract. It is an unusual cause of infection and when it is cultured, it is most usually found mixed with other organisms. Infections most commonly occur in patients with cancers of the head and neck,[2] but it is also common in human bite infections, especially "reverse bite" or "fight bite", or "clenched fist injuries".[3] It also causes infections in insulin-dependent diabetics and intravenous drug users who lick their needles ("needle-licker's osteomyelitis").[4] It is one of the HACEK group of infections which are a cause of culture-negative endocarditis.

E. corrodens infections are typically indolent (the infection does not become clinically evident until a week or more after the injury). They also mimic anaerobic infection in being extremely foul-smelling.


E. corrodens can be treated with penicillins, cephalosporins, or tetracyclines. It is innately resistant to macrolides (e.g., erythromycin), clindamycin, and metronidazole). It is susceptible to fluoroquinolones (e.g., ciprofloxacin) in vitro, but no clinical evidence is available to advocate their use in these infections.

In popular culture[edit]

E. corrodens is mentioned in The Tennis Partner, a memoir by Abraham Verghese.[5]

It is also mentioned in Episode 22, "Punch line" of the sixth season of the television docudrama, "Forensic Files."

It is also mentioned in Season 3, Episode 8, "Whac-A-Mole" (at 20:51 min) of the TV show House, M.D.


  1. ^ Eiken M (1958). "Studies on an anaerobic, rod-shaped, gram-negative microorganism: Bacteroides corrodens N. sp.". Acta Pathol Microbiol Scand 43: 404–16. doi:10.1111/j.1699-0463.1958.tb04677.x. 
  2. ^ Sheng WS, Hsueh PR, Hung CC; et al. (2001). "Clinical features of patients with invasive Eikenella corrodens infections and microbiological characteristics of the causative isolates". Eur J Clin Microbiol Infect Dis 20 (4): 231–6. doi:10.1007/s100960100477. PMID 11399011. 
  3. ^ Goldstein EJC. (1992). "Bite wounds and infections". Clin Infect Dis 14 (3): 633–40. doi:10.1093/clinids/14.3.633. PMID 1562653. 
  4. ^ Swisher LA, Roberts JR, Glynn MJ. (1994). "Needle licker's osteomyelitis". Am J Emerg Med 12: 343–6. doi:10.1016/0735-6757(94)90156-2. PMID 8179747. 
  5. ^ Verghese, Abraham (1998). The Tennis Partner, pg 61-62. Harper Perennial. p. 345. ISBN 0-06-093113-2. 

6. Azakami H., Teramura I, Matsunaga T, Akimichi H, Noiri Y, Ebisu S, Kato A.(Aug,2006).Characterization of autoinducer 2 signal in Eikenella corrodens and its role in biofilm formation. J Biosci Bioeng;102(2):110-7.http://www.ncbi.nlm.nih.gov/pubmed/?term=Characterization+of+autoinducer+2+signal+in+Eikenella+corrodens+and+its+role+in+biofilm+formation

7. Karim MM1, Nagao A, Mansur FJ, Matsunaga T, Akakabe Y, Noiri Y, Ebisu S, Kato A, Azakami H. Biosci Biotechnol Biochem (2013). The periodontopathogenic bacterium Eikenella corrodens produces an autoinducer-2-inactivating enzyme;77(5):1080-5.http://www.ncbi.nlm.nih.gov/pubmed/?term=The+periodontopathogenic+bacterium+Eikenella+corrodens+produces+an+autoinducer-2-inactivating+enzyme

8. Karim MM1, Hisamoto T, Matsunaga T, Asahi Y, Noiri Y, Ebisu S, Kato A, Azakami H (Sep, 2013).LuxS affects biofilm maturation and detachment of the periodontopathogenic bacterium Eikenella corrodens.J Biosci Bioeng;116(3):313-8 http://www.ncbi.nlm.nih.gov/pubmed/?term=LuxS+affects+biofilm+maturation+and+detachment+of+the+periodontopathogenic+bacterium+Eikenella+corrodens

External links[edit]