铜绿假单胞菌脂多糖对阿萨希毛孢子菌生物膜形成的影响

Effect of Pseudomonas aeruginosa lipopolysaccharide on the biofilm formation of Trichosporon asahii

目的研究铜绿假单胞菌脂多糖(LPS)对阿萨希毛孢子菌生物膜形成的影响。方法将不同浓度(100~0.1μg/mL)铜绿假单胞菌脂多糖与阿萨希毛孢子菌共培养后,利用倒置显微镜观察生物膜的形态学变化,并利用甲基四氮盐(XTT)减低法检测不同时间点生物膜生成量的变化。结果与生长对照组相比,实验组铜绿假单胞菌LPS对阿萨希毛孢子菌生物膜的生成具有菌株差异性和LPS浓度依赖性。其中,黏附阶段(2h),各浓度组铜绿假单胞菌LPS对生物膜形成的影响没有统计学差异。生物膜形成阶段(24h),与生长对照比,100μg/mL、10μg/mL、1μg/mL的铜绿假单胞菌LPS对阿萨希毛孢子菌的生物膜形成的抑制作用均有统计学意义作用。而在生物膜成熟阶段(48h),只有100μg/mL的铜绿假单胞菌LPS对阿萨希毛孢子菌的生物膜形成的抑制作用具有统计学意义。倒置显微镜下,实验组菌丝形成明显受到抑制,以孢子相为主。结论铜绿假单胞菌脂多糖可以通过抑制阿萨希毛孢子菌菌丝的形成来减少生物膜的形成,并且抑制作用具有时间和浓度依赖性,以24h时,100μg/mL作用最为显著。

Objective To explore the effect of Pseudornonas aeruginosa lipopolysaccharide on the biofilm formation of Tri- chosporon asahii.Methods Morphological changes of the cells were observed by inverted microscope.And XTT reduction as- say was used to elucidate the effect of Pseudomonas aeruglnosa lipopolysaccharide （LPS）（100-0.1μg/mL） on biofilm forma- tion of Trichosporon asahii. Results Compared with the growth group, the biofilm formation of Trichosporon asahii was modulated by the Pseudomonas aeruginosa LPS （the experimental group） in a time and concentration dependent manner. During the adhesion stage （2 h）,the difference between the growth group and all exlaerimental groups was not statistically significant.While during the biofilm formation stage （24 h）, the biofilm formation could be inhibited statistically significant when the concentration of LPS was 100 μg/mL, 10 μg/mL and 1 μg/mL.And under the biofilm maturation stage,only when the LPS was 100 μg/mL, the difference between the growth group and the experimental group was significantly different. Meanwhile,when the inhibition exhibited,the hyphal formation was obviously inhibited, mainly in the spore phase under the inverted microscope.Conclusions Pseudomonas aeruginosa LPS could inhibit the Trichosporon asahii biofilm formation in a time and concentration dependent manner.And the inhibitory effect was achieved through reducing the hyphal formation, es- pecially in 24 h,100μg/mL.