Streptococcus mutans adherence: presumptive evidence for protein-mediated attachment followed by glucan-dependent cellular accumulation.
Streptococcus mutans adherence: presumptive evidence for protein-mediated attachment followed by glucan-dependent cellular accumulation.
复制标题
变形链球菌粘附：蛋白质介导的粘附以及随后的葡聚糖依赖性细胞积累的推定证据。
作者：
R. H. Staat;S. Langley;R. Doyle
变形链球菌对光滑表面的粘附归因于蔗糖衍生的d-葡聚糖的产生。然而，一些研究表明，细菌将在没有蔗糖的情况下粘附。目前的数据证实S.在不存在蔗糖的情况下，变形杆菌对唾液包被的羟基磷灰石珠的粘附由朗缪尔方程描述。蔗糖独立的粘附的性质进行了研究与梨美洲凝集素作为选择性粘附抑制剂。用美洲青霉凝集素对细菌进行预处理，导致粘附性降低10倍，并且加入蔗糖后，这种抑制作用不会逆转。S.与蔗糖含量无关，用蛋白酶处理变形杆菌也降低了粘附，而细菌的高碘酸盐氧化和葡聚糖水解酶处理将蔗糖介导的粘附降低到蔗糖非依赖性粘附的水平。美洲大蠊凝集素、葡聚糖水解酶和胃蛋白酶预处理细胞不能消除蔗糖诱导的凝集。扫描电子显微镜显示，短链球菌链结合唾液包被的羟基磷灰石晶体中的蔗糖独立的系统，而蔗糖的存在下，导致更大的细菌团块被发现。从这些数据中得出了变异株的粘附性。有人提出，其中一个反应是附着到牙表膜，这是介导的细胞表面蛋白质，而不是葡聚糖或磷壁酸。另一种反应是由蔗糖衍生的d-葡聚糖和细胞表面凝集素介导的细胞积累。一系列以美洲黑杨凝集素为选择性抑制剂的序贯粘附实验为我们的模型的有效性提供了假定证据。变形菌粘附。
Adherence of Streptococcus mutans to smooth surfaces has been attributed to the production of sucrose-derived d-glucans. However, several studies indicate that the bacterium will adhere in the absence of sucrose. The present data confirmed that S. mutans adherence to saliva-coated hydroxyapatite beads in the absence of sucrose is described by the Langmuir equation. The nature of the sucrose-independent adherence was studied with the Persea americana agglutinin as a selective adherence inhibitor. Pretreatment of the bacterium with P. americana agglutinin caused a 10-fold reduction in adherence, and the inhibition was not reversed with the addition of sucrose. Pretreatment of S. mutans with proteases also reduced adherence, regardless of the sucrose content, whereas periodate oxidation and glucanohydrolase treatment of the bacteria reduced sucrose-mediated adherence to the levels found for sucrose-independent adherence. The P. americana agglutinin, glucanohydrolase, and pepsin pretreatment of the cells did not eliminate sucrose-induced agglutination. Scanning electron microscopy showed that short streptococcal chains were bound to saliva-coated hydroxyapatite crystals in the sucrose-independent system, whereas the presence of sucrose caused larger bacterial clumps to be found. A two-reaction model of S. mutans adherence was developed from these data. It is proposed that one reaction is attachment to the tooth pellicle which is mediated by cell-surface proteins rather than glucans or teichoic acids. The other reaction is cellular accumulation mediated by sucrose-derived d-glucans and cell surface lectins. A series of sequential adherence experiments with P. americana agglutinin as a selective inhibitor provided presumptive evidence for the validity of our model of S. mutans adherence.