变形链球菌葡糖基转移酶过度表达株粘附特征的研究

Adherence and Insoluble Glucan Synthesis of Streptococcus mutans Glucosyltransferase Overexpression Mutants

葡糖基转移酶在介导变形链球菌对牙面的粘附过程中起着十分重要的作用。本文对变形链球菌葡糖基转移酶野生菌株、缺陷株和过度表达株对牙面的粘附特征和非水溶性葡聚糖合成能力进行了研究。结果表明：变形链球菌野生型ＭＴ８１４８和变形链球菌ＣＡＧＴａｓｅ缺陷株Ｂ２９对牙面的粘附水平、非水溶性葡聚糖合成量与接种量无关；过度表达株Ｂ２９（ｐＺＢ１）－４，Ｂ２９（ｐＺＢ１）－１１及Ｂ２９（ｐＺＢ１）－３３随接种量的增加对牙面的粘附水平下降，但非水溶性葡聚糖合成增加。

Glucosyltransferases play an important role regulating Streptococcus mutans adherence to tooth surface. In this study sucrose dependent adherence and insoluble glucan (ISG) synthesis by S. mutans MT8148, its CAGTase deficient mutant B29, CAGTase overexpression mutants B29 (pZB1)-11 and B29 (pZB1)-33 at different amount of inoculum was determined. The result showd that the adherence ability of B29 was decreased dramatically in both low and high amount of inoculum. However, the CAGTase overexpression mutants exhibited more ISG synthesis and lower adherence ability at high amount inoculum. This result indicates that ISG over synthesis may interfere firm adherence of S. mutans.