|
''Streptococcus mutans'' is facultatively anaerobic, Gram-positive coccus-shaped bacterium commonly found in the human oral cavity and is a significant contributor to tooth decay. It is part of the "streptococci" (plural, non-italic lowercase), an informal general name for all species in the genus ''Streptococcus'' (capitalized, italic due to its being the formal name).The microbe was first described by J Kilian Clarke in 1924. This bacterium, along with the closely related species ''Streptococcus sobrinus'', can cohabit the mouth: Both contribute to oral disease, and the expense of differentiating them in laboratory testing is often not clinically necessary. Therefore, for clinical purposes they are often considered together as a group, called the mutans streptococci (plural, non-italic due to it being an informal group name). This grouping of similar bacteria with similar tropism can also be seen in the viridans streptococci, another group of ''Streptococcus'' species. ==Introduction== ''Streptococcus mutans'' is a Gram-positive bacterium that is the primary causative agent in the formation of dental cavities in humans. Gram-positive bacteria are those that are stained dark-blue or violet by Gram staining. This is based on the physical properties of their cell walls, as opposed to gram-negative bacteria, which cannot retain the crystal violet stain. ''Streptococcus'' is a genus of spherical Gram-positive bacteria belonging to the phylum Firmicutes and the lactic acid bacteria group. ''S. mutan''s, a member of the human oral flora, is widely recognized as the main causative agent of dental cavities. Conditions in the oral cavity are diverse and complex, frequently changing from one extreme to another. Thus, to survive in the oral cavity, ''S. mutans'' must tolerate rapidly harsh environmental fluctuations and exposure to various antimicrobial agents to survive. However, the mechanisms under which this cariogenic pathogen can survive and proliferate under such extreme environmental conditions are largely unknown, as little research has been done on this matter. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Streptococcus mutans」の詳細全文を読む スポンサード リンク
|