密度感应分子对白色念珠菌生物被膜形成作用的研究

目的:白色念珠菌生物被膜形成受密度感应分子调控,法尼醇和酪醇是白色念珠菌产生的两种密度感应分子?本研究探讨不同生物被膜时相,密度感应分子对白色念珠菌形态及生物被膜形成的作用?方法:体外构建白色念珠菌生物被膜?研究分为法尼醇处理组?酪醇处理组?法尼醇和酪醇联合处理组?对照组?首先采用XTT检测不同生物被膜时相酪醇和法尼醇对白色念珠菌细胞活力的作用?扫描电子显微镜(scanning electron microscopy,SEM)观察酪醇和法尼醇对白色念珠菌生物被膜的作用?同时采用气相色谱-质谱联用(gas chromatography-mass spectrometry,GC/MS)检测白色念珠菌生物被膜法尼醇的产生,高效液相色谱(high press liquid chromograph,HPLC)检测白色念珠菌生物被膜酪醇的产生?结果:XTT结果显示,与对照组比较,酪醇可促进6 h白色念珠菌生物膜活力(P < 0.05),法尼醇抑制早期(3 h和6 h)生物被膜活力(P < 0.05),联合作用组抑制6 h生物被膜活力(P < 0.001)?扫描电镜观察发现,酪醇促进3 h和6 h白色念珠菌细胞的出芽,法尼醇抑制3 h和6 h菌丝形成,两者联合作用以后者对菌丝形成的抑制作用为主?GC/MS及 HPLC结果表明在早期(3 h和6 h)生物被膜,2种密度感应分子产生少且无明显升高趋势(P > 0.05);随着生物被膜成熟(24 h及36 h),酪醇产生明显增多(P < 0.05),法尼醇产生也明显增多(P < 0.05)?24 h生物被膜产生酪醇最多,36 h 生物被膜产生法尼醇最多?结论:酪醇可以促进白色念珠菌出芽和菌丝伸长,促进早期生物被膜形成?法尼醇抑制出芽和菌丝形成,抑制早期生物被膜形成?两者联合作用以法尼醇对菌丝形成的抑制作用为主?

Effects of quorum sensing molecule on the morphology in Candida albicans biofilm

Objective:Quorum sensing regulates the formation of Candida albicans (C. albicans) biofilm. Farnesol and tyrosol are quorum sensing molecules produced by C. albicans. The aim of this study is to find the effects of quorum sensing molecules on the formation of C. albicans and biofilm in different time phases of biofilm. Methods:C. albicans biofilm was constructed in vitro. The study C. albicans biofilm were separated into the tyrosol treated group,the arnesol treated group,the tyrosol and farnesol co-treated group and the no-treated control group. The effects of the tyrosol and farnesol on C. albicans cell viability in different time phases were detected by XTT method. The effects of the tyrosol and farnesol on C. albicans biofilm formation were observed by scan electronic microscope (SEM). The production of farnesol and tyrosol of biofilms was detected by gas chromatography-mass spectrometry (GC/MS) and high press liquid chromograph (HPLC),respectively. Results:The XTT method suggested that biolfilm activitity was promoted by tyrosol at 6 h (P < 0.05),while it was suppressed by farnesol at 3 h and 6 h (P < 0.05). Biofilm activity of the tyrosol and farnesol co-treated group was inhibited at 6 h (P < 0.001). The SEM observations showed that tyrosol contributed to the germ tube formation of the C. albicans biofilm at 3 h and 6 h. Farnesol inhibited the hyphae growth of biofilm at 3 h and 6 h. The tyrosol and farnesol co-treated group showed that the effect of tyrosol was not antagonistic to that of farnesol. GC/MS and HPLC results showed that C. albicans produced little tyrosol and farnesol at early stage and showed no obvious rising trend (P > 0.05). With biofilm maturation (24 h and 36 h),the production of tyrosol increased significantly (P < 0.05),which of farnesol was also increased significantly (P < 0.05). In all,C. albicans produced most tyrosol at 24 h and most farnesol at 36 h. Conclusion:Tyrosol contributed to the biofilm formation by increasing the germ tube formation of the C. albicans biofilm. Farnesol inhibited the C.albicans biofilm formation by decreasing the germ tube formation. The inhibition of farnesol to the hyphae growth was more powerful than the contribution of tyrosol to the germ tube growth in the co-treated studies.