Golub E E, Thaler M, Davis C, Malamud D
Infect Immun. 1979 Dec;26(3):1028-34. doi: 10.1128/iai.26.3.1028-1034.1979.
Two new assays for saliva-mediated aggregation of oral bacteria have been developed, based on the use of [3H]thymidine-labeled cells. One assay separates free cells from aggregated cells by centrifugation through sucrose, whereas the other utilizes membrane filters (8 micrometers, Nuclepore) to effect the separation. Comparison of these assays with the turbidity method reveals that they are faster (X20 to 40) and require 10 times less saliva and bacteria. The aggregation of Streptococcus sanguis M5, as determined with these assays, is complete in 5 min and is dose dependent on added cells and saliva. The reaction exhibits a temperature optimum of 42 degrees C with no reaction at 0 degrees C. If the pH is reduced to below 5, saliva-dependent aggregation is inhibited. The salivary factor(s) are heat labile, losing 100% of their activity after 100 degrees C, 10 min or 70 degrees C, 30 min.
基于使用[3H]胸苷标记的细胞，已开发出两种用于唾液介导的口腔细菌聚集的新检测方法。一种检测方法是通过蔗糖离心将游离细胞与聚集细胞分离，而另一种方法则利用膜过滤器（8微米，核孔滤膜）进行分离。将这些检测方法与比浊法进行比较发现，它们速度更快（快20到40倍），所需的唾液和细菌量少10倍。用这些检测方法测定，血链球菌M5的聚集在5分钟内完成，且与添加的细胞和唾液呈剂量依赖性。该反应的最适温度为42℃，在0℃时无反应。如果pH值降至5以下，唾液依赖性聚集会受到抑制。唾液因子对热不稳定，在100℃、10分钟或70℃、30分钟后会失去100%的活性。
