Bacteroides

Bacteroides
"Bacteroides biacutis" anaerobically cultured in blood agar medium
Bacteroides biacutis anaerobically cultured in blood agar medium
Scientific classification Edit this classification
Domain: Bacteria
Phylum: Bacteroidota
Class: Bacteroidia
Order: Bacteroidales
Family: Bacteroidaceae
Genus: Bacteroides
Castellani & Chalmers 1919[1]
Species

Bacteroides is a genus of Gram-negative, obligate anaerobic bacteria. Bacteroides species are non endospore-forming bacilli, and may be either motile or nonmotile, depending on the species.[3] The DNA base composition is 40–48% GC. Unusual in bacterial organisms, Bacteroides membranes contain sphingolipids. They also contain meso-diaminopimelic acid in their peptidoglycan layer.

Bacteroides species are normally mutualistic, making up the most substantial portion of the mammalian gastrointestinal microbiota,[4] where they play a fundamental role in processing of complex molecules to simpler ones in the host intestine.[5][6][7] As many as 1010–1011 cells per gram of human feces have been reported.[8] They can use simple sugars when available; however, the main sources of energy for Bacteroides species in the gut are complex host-derived and plant glycans.[9] Studies indicate that long-term diet is strongly associated with the gut microbiome composition—those who eat a higher proportion of protein and animal fats have predominantly Bacteroides bacteria, while for those who consume more carbohydrates or fiber the Prevotella species dominate.[10]

One of the most important clinically is Bacteroides fragilis.[11][12]

Bacteroides melaninogenicus has recently been reclassified and split into Prevotella melaninogenica and Prevotella intermedia.[13]

  1. ^ Castellani, A., and Chalmers, A.J. Manual of Tropical Medicine, 3rd ed. (1919). Williams Wood and Co., New York.
  2. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am an ao Parte AC. "Bacteroides". LPSN. Archived from the original on 2020-11-24. Retrieved 2020-02-19.
  3. ^ Madigan M, Martinko J, eds. (2005). Brock Biology of Microorganisms (11th ed.). Prentice Hall. ISBN 978-0-13-144329-7.
  4. ^ Dorland WA, ed. (2003). Dorland's Illustrated Medical Dictionary (30th ed.). W.B. Saunders. ISBN 978-0-7216-0146-5.
  5. ^ Wexler HM (October 2007). "Bacteroides: the good, the bad, and the nitty-gritty". Clinical Microbiology Reviews. 20 (4): 593–621. doi:10.1128/CMR.00008-07. PMC 2176045. PMID 17934076.
  6. ^ Xu J, Gordon JI (September 2003). "Honor thy symbionts". Proceedings of the National Academy of Sciences of the United States of America. 100 (18): 10452–10459. Bibcode:2003PNAS..10010452X. doi:10.1073/pnas.1734063100. PMC 193582. PMID 12923294.
  7. ^ Xu J, Mahowald MA, Ley RE, Lozupone CA, Hamady M, Martens EC, et al. (July 2007). "Evolution of symbiotic bacteria in the distal human intestine". PLOS Biology. 5 (7): e156. doi:10.1371/journal.pbio.0050156. PMC 1892571. PMID 17579514.
  8. ^ Finegold SM, Sutter VL, Mathisen GE (1983). Normal indigenous intestinal flora (pp. 3-31) in Human intestinal microflora in health and disease. Academic Press. ISBN 978-0-12-341280-5.
  9. ^ Martens EC, Chiang HC, Gordon JI (November 2008). "Mucosal glycan foraging enhances fitness and transmission of a saccharolytic human gut bacterial symbiont". Cell Host & Microbe. 4 (5): 447–457. doi:10.1016/j.chom.2008.09.007. PMC 2605320. PMID 18996345.
  10. ^ Wu GD, Chen J, Hoffmann C, Bittinger K, Chen YY, Keilbaugh SA, et al. (October 2011). "Linking long-term dietary patterns with gut microbial enterotypes". Science. 334 (6052): 105–108. Bibcode:2011Sci...334..105W. doi:10.1126/science.1208344. PMC 3368382. PMID 21885731.
  11. ^ Appleman MD, Heseltine PN, Cherubin CE (Jan 1990). "Epidemiology, antimicrobial susceptibility, pathogenicity, and significance of Bacteroides fragilis group organisms isolated at Los Angeles County-University of Southern California Medical Center". Reviews of Infectious Diseases. 13 (1): 12–18. doi:10.1093/clinids/13.1.12. PMID 2017610.
  12. ^ Sears CL (April 2009). "Enterotoxigenic Bacteroides fragilis: a rogue among symbiotes". Clinical Microbiology Reviews. 22 (2): 349–69, Table of Contents. doi:10.1128/CMR.00053-08. PMC 2668231. PMID 19366918.
  13. ^ "Bacteroides Infection: Overview - eMedicine". Archived from the original on 22 December 2008. Retrieved 2008-12-11.