论文部分内容阅读
目的:应用激光共聚焦显微镜观察clpP基因对变形链球菌生物膜耐酸性的影响。方法:将变形链球菌标准株UA159和它的clpP基因缺陷株分别做成预酸化和致死酸化处理的菌液,接种于刻有宽500μm深500μm沟的羟基磷灰石圆片上厌氧培养12 h。培养后取出圆片,所有圆片均在处理后立刻进行荧光死、活菌斑染色并行共聚焦观察。测算活菌厚度、面积及荧光强度占总菌斑的百分比,应用SPSS 15.0统计软件,采用方差分析及均数两两比较分析clpP基因缺失对细菌生长及耐酸能力的变化。结果:共聚焦显微镜下,clpP基因缺失菌株所形成的生物膜菌斑厚度略薄于标准菌株(P<0.05),经过预酸化处理和致死酸处理后clpP基因缺失菌株所形成的生物膜菌斑厚度显著薄于标准菌株(P<0.01),而且活菌百分比显著低于标准株(P<0.01)。结论:共聚焦显微镜下clpP基因可以显著地降低变形链球菌的耐酸能力,并一定程度地降低变形链球菌的生长能力。
Objective: To observe the effect of clpP gene on the acid resistance of Streptococcus mutans biofilm by laser confocal microscopy. Methods: The mutated Streptococcus mutans strain UA159 and its clpP gene-deficient strain were made into pre-acidified and lethal acid-treated bacterium, and then inoculated on hydroxyapatite discs engraved with a width of 500μm and depth of 500μm for 12 h . After incubation, the disks were removed and all the disks were fluorescently killed immediately after treatment. Live plaque staining was performed in parallel with confocal observation. The percentage of viable cells, the area and fluorescence intensity of the total plaque were calculated. SPSS15.0 statistical software was used to analyze the changes of bacterial growth and acid resistance by the analysis of variance and the mean of pairwise comparison. Results: Under the confocal microscope, the plaque thickness of the biofilm formed by the clpP gene deletion strain was slightly thinner than that of the standard strain (P <0.05). The biofilm plaque formed by the clpP gene deletion strain after pre-acidification and lethal acid treatment The thickness was significantly thinner than the standard strain (P <0.01), and the percentage of viable cells was significantly lower than the standard strain (P <0.01). Conclusion: The clpP gene can significantly reduce the acid resistance of Streptococcus mutans and reduce the growth of Streptococcus mutans to a certain degree under the confocal microscope.