Streptococcus mutans
From Wikipedia, the free encyclopedia
 |
||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
 Gram stain of S. mutans in thioglycollate broth culture.
|
||||||||||||||
| Scientific classification | ||||||||||||||
|
||||||||||||||
|
|
||||||||||||||
| Streptococcus mutans Clarke 1924 |
Streptococcus mutans is a Gram-positive, facultatively anaerobic bacteria commonly found in the human oral cavity and is a significant contributor to tooth decay.[1][2] The microbe was first described by Clarke in 1924.[3]
Contents |
[edit] Role in tooth decay
Along with S. sobrinus, S. mutans plays a major role in tooth decay, metabolizing sucrose to lactic acid.[2] The acidic environment created in the mouth by this process is what causes the highly mineralized tooth enamel to be vulnerable to decay. S. mutans is one of a few specialized organisms equipped with receptors for adhesion to the surface of teeth. Sucrose is utilized by S. mutans to produce a sticky, extracellular, dextran-based polysaccharide that allows them to cohere to each other forming plaque. S. mutans produces dextran via the enzyme dextransucrase (a hexosyltransferase) using sucrose as a substrate in the following reaction:
- n sucrose → (glucose)n + n fructose
Sucrose is the only sugar that S. mutans can use to form this sticky polysaccharide.[1]
Conversely, many sugars—glucose, fructose, lactose, sucrose—can be digested by S. mutans, but they produce lactic acid as an end product. It is the combination of plaque and acid that leads to dental decay.[4]
[edit] See also
[edit] References
- ^ a b Ryan KJ; Ray CG (editors) (2004). Sherris Medical Microbiology, 4th ed., McGraw Hill. ISBN 0-8385-8529-9.
- ^ a b Loesche WJ (1996). Microbiology of Dental Decay and Periodontal Disease. In: Baron's Medical Microbiology (Baron S et al, eds.), 4th ed., Univ of Texas Medical Branch. (via NCBI Bookshelf) ISBN 0-9631172-1-1.
- ^ Clarke, JK (1924). "On the bacterial factor in the etiology of dental caries". Brit J Exp Pathol 5: 141–7.
- ^ Madigan M; Martinko J (editors). (2005). Brock Biology of Microorganisms, 11th ed., Prentice Hall. ISBN 0-13-144329-1.
[edit] External links
 |
This bacteria-related article is a stub. You can help Wikipedia by expanding it. |
