Duggan Jason M, Sedgley Christine M
Department of Cariology, Restorative Sciences and Endodontics, The University of Michigan, School of Dentistry, Ann Arbor, Michigan 48109-1078 , USA.
J Endod. 2007 Jul;33(7):815-8. doi: 10.1016/j.joen.2007.02.016. Epub 2007 Apr 16.
Biofilms are complex aggregations of microorganisms attached to a surface. The formation of biofilms might facilitate certain survival and virulence characteristics under some situations. This study tested the hypothesis that the ability of Enterococcus faecalis to form biofilms is related to the source of the strains. E. faecalis strains recovered from root canals (n = 33), the oral cavity (n = 21), and non-oral/non-endodontic sources (n = 16) were studied. Biofilms were grown in tryptic soy broth in 96-well plates for 24 hours at 37 degrees C, fixed with Bouin's fixative, and stained with 1% crystal violet. Optical density at 570 nm (OD(570)) was measured by using a microtiter plate reader. Experiments were performed in quadruplicate on three occasions and mean OD(570) readings determined for each strain. There were no statistically significant differences between groups (p = 0.066, Kruskal-Wallis). Within the root canal and oral isolates there were no significant associations between biofilm formation and the presence of the virulence determinants asa, cylA, esp, and gelE.
生物膜是附着于表面的微生物的复杂聚集体。在某些情况下，生物膜的形成可能有助于某些生存和致病特性。本研究检验了粪肠球菌形成生物膜的能力与菌株来源相关这一假设。对从根管（n = 33）、口腔（n = 21）和非口腔/非牙髓来源（n = 16）分离出的粪肠球菌菌株进行了研究。生物膜在胰蛋白胨大豆肉汤中于96孔板中在37℃下培养24小时，用布因氏固定液固定，并用1%结晶紫染色。使用酶标仪测量570nm处的光密度（OD(570)）。实验在三个不同时间重复进行四次，并确定每个菌株的平均OD(570)读数。各组之间无统计学显著差异（p = 0.066，Kruskal-Wallis检验）。在根管和口腔分离株中，生物膜形成与毒力决定因素asa、cylA、esp和gelE的存在之间无显著关联。
