Graves W, Verran J
Microbios. 1984;40(161-162):145-52.
Sucrose-induced aggregation of Streptococcus mutans was ascertained by measuring the decrease in optical density of a cell suspension after 20 h incubation. The optimum sucrose concentration for the aggregation assay was 5% w/v, at an incubation temperature of 37 degrees C. Dextranase and protease enzymes were added to the suspensions to determine their effects on aggregation. Dextranase treatment decreased aggregation. Electron microscopic studies revealed a reduction in the amount of a diffuse coat which surrounded cells in the absence of the enzyme but in the presence of sucrose, and a degradative effect on fibrous extracellular material. Protease treatment of suspensions produced an increase in optical density; cell aggregates were not apparent. Electron microscopic studies revealed extensive cell damage and lysis. The success of these enzymes in decreasing aggregation would indicate a role in both caries and plaque control in vivo.
通过测量细胞悬液在37℃孵育20小时后的光密度降低来确定蔗糖诱导的变形链球菌聚集。聚集测定的最佳蔗糖浓度为5%（w/v），孵育温度为37℃。向悬液中加入葡聚糖酶和蛋白酶以确定它们对聚集的影响。葡聚糖酶处理降低了聚集。电子显微镜研究显示，在没有酶但有蔗糖的情况下，围绕细胞的弥漫性被膜的量减少，并且对纤维状细胞外物质有降解作用。蛋白酶处理悬液导致光密度增加；细胞聚集体不明显。电子显微镜研究显示广泛的细胞损伤和裂解。这些酶在降低聚集中的成功表明它们在体内龋齿和牙菌斑控制中都发挥作用。
