| 摘要: |
| 目的 探讨铜绿假单胞菌中Ⅵ型分泌系统（T6SS）和群体感应（QS）系统在铜绿假单胞菌生物被膜形成中的作用。方法 将铜绿假单胞菌生物被膜阳性的模式菌株PAO1制备成生物被膜菌和浮游菌。采用实时荧光定量PCR法检测菌株中T6SS相关溶血素共调节蛋白（Hcp）基因Hcp1、Hcp2和Hcp3，QS系统相关基因LasR，胞外多糖相关多糖合成位点基因A（PslA）和菌膜基因A（PelA），以及Ⅳ型菌毛基因（PilA）和鞭毛蛋白基因（FliC）的表达水平。采用独立样本t检验比较PAO1生物被膜菌与浮游菌中上述基因表达的差异。结果 PAO1生物被膜菌PslA、PelA、PilA和FliC基因的相对表达量均明显高于浮游菌，分别为浮游菌的714、274、604和42倍（P均<0.05），提示制备的PAO1生物被膜菌形成了具有鞭毛和菌毛结构的成熟生物被膜。PAO1生物被膜菌Hcp1、Hcp2、Hcp3和LasR基因的相对表达量均明显高于浮游菌，分别为浮游菌的1 045、11 268、6 654和1 226倍（P均<0.05），提示T6SS和QS系统与PAO1菌生物被膜的形成有关。结论 铜绿假单胞菌中T6SS和QS系统可能参与生物被膜形成，其具体调控机制有待进一步研究。 |
| 关键词: 铜绿假单胞菌 Ⅵ型分泌系统 群体感应系统 生物被膜 |
| DOI：10.16781/j.0258-879x.2019.07.0732 |
| 投稿时间：2019-02-18修订日期：2019-07-08 |
| 基金项目: |
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| Type Ⅵ secretion system and quorum sensing system involved in biofilm formation in Pseudomonas aeruginosa |
| ZOU Ya-ru1,LI Ying1,WU Yong2*,WANG Huai-zhou1* |
(1. Department of Laboratory Medicine, Changhai Hospital, Naval Medical University(Second Military Medical University), Shanghai 200433, China;
2. Department of Laboratory Medicine, The Third Xiangya Hospital, Central South University, Changsha 410013, Hunan, China
*Corresponding authors) |
| Abstract: |
| Objective To explore the roles of type Ⅵ secretion system (T6SS) and quorum sensing (QS) system in the biofilm formation in Pseudomonas aeruginosa. Methods The PAO1 biofilm bacteria and planktonic bacteria were established. The expression levels of T6SS associated genes hemolysin co-regulated protein (Hcp) gene (Hcp1, Hcp2, Hcp3), QS associated gene LasR, exopolysaccharide associated genes polysaccharide synthesis locus A (PslA) and pellicle A (PelA), type Ⅳ pili gene pilus A (PilA) and flagellin C (FliC) were detected by quantitative real-time PCR, and the expression levels of those genes were compared between PAO1 biofilm bacteria and planktonic bacteria using independent t-test. Results The expression levels of PslA, PelA, PilA and FliC genes in PAO1 biofilm bacteria were respectively 714, 274, 604 and 42 folds of those in the planktonic bacteria (all P<0.05), suggesting that PAO1 bacteria formed mature biofilm with flagellum and pili. The expression levels of Hcp1, Hcp2, Hcp3, and LasR genes in PAO1 biofilm bacteria were respectively 1 045, 11 268, 6 654 and 1 226 folds of those in planktonic bacteria (all P<0.05), suggesting that T6SS and QS systems were related to the biofilm formation of PAO1 bacteria. Conclusion T6SS and QS systems might be involved in biofilm formation in Pseudomonas aeruginosa, and its regulatory mechanism needs further study. |
| Key words: Pseudomonas aeruginosa type Ⅵ secretion system quorum sensing system biofilms |
