摘要
目的:探讨变异链球菌IngbrittC(血清C型)国际标准株与LuxS基因缺失的变异链球菌突变株之间生物被膜的形成差异。方法:分别将变异链球菌标准株和LuxS基因突变株接种于含有2%葡萄糖、2%蔗糖的乳酪消化胨酵母(TPY)液体培养基中,以牙釉质磨片为载体,于扫描电镜下观察形成24h的上述两菌株生物被膜。结果:(1)当以葡萄糖作为补充糖源时,变异链球菌标准株和LuxS基因突变株所形成的生物被膜表现型未见明显差异;(2)当以蔗糖作为补充糖源时,两菌株所形成的生物被膜有明显的不同,标准株生物被膜相对平滑均质,而LuxS基因突变株的生物被膜呈松散的蜂房状,基质间有较大的间隙,形成较大的团簇状菌落;(3)加入标准株的无菌体上清液可以使LuxS基因突变株的生物被膜表型部分恢复正常,提高LuxS基因突变株形成生物被膜的能力。结论:变异链球菌标准株和LuxS基因突变株均能形成生物被膜,但LuxS基因突变株的生物被膜结构发生改变;依赖于LuxS的群体感应系统会影响变异链球菌生物被膜的形成。
Objective: To study the difference of biofilm formation between Streptococcus mutans Ingbritt C international standard strain and LuxS mutant strain. Methods: Both Streptococcus mutans standard strain and LuxS mutant strain were cultured in TPY liquid medium containing glucose or sucrose in 2% concentration by enamel slabs,and then Twenty-four-hour biofilms of the two strains were observed using scanning electron microscope. Results: ( 1)The LuxS mutant showed no significant qualitative difference in the biofilm phenotypes compared to the Streptococcus mutans standard strain in the medium supplemented with 2%glucose; (2)In contrast,the LuxS mutant formed bilfilms that markedly differed from the standard strain when grown with 2% sucrose.The biofilms of standard strain appeared smooth and more evenly distributed,whereas the biofilms formed by the LuxS mutant were loose,hive-like,and had large gaps between the biofilm matrix,and the cell aggregates appeared muth larger;, (3)The mutant phenotypes were Complemented partly by exposure to supernatants with no cells from standard strain cultures,and the capacity of mutant strain to form bilfilms was enhanced. Conclusion: Both Streptococcus mutans standard strain and LuxS mutant strain can form the biofilms,but the architecture of biofilms formed by the LuxS mutant appears to be altered; LuxS-Based quorum sensing could affect Streptococcus mutans biofilm formation.
出处
《天津医科大学学报》
2009年第4期546-550,共5页
Journal of Tianjin Medical University
基金
天津市自然科学基金资助项目(06YFJMJC06900)