中文摘要：

目的 在中药中筛选并研究铜绿假单胞菌（Pseudomonas aeruginosa,PA）群体感应系统抑制物（quorum-sensing inhibitor,QSI）.方法 利用铜绿假单胞菌QS系统相关基因lasI、lasR、rhlI和rhlR的启动子与报道子荧光素酶（Luciferase）基因IuxCDABE的融合子为筛选系统,通过检测化学发光反应不同中药对群体感应系统基因表达的影响,并检测中药对铜绿假单胞菌毒性相关表型的影响.结果 研究结果表明中药半枝莲的水提物在不影响铜绿假单胞菌生长的条件下,可抑制PA中QS系统基因lasI、lasR、rhlI和rhlR的表达,并可抑制铜绿假单胞菌的运动性.结论 中药半枝莲对铜绿假单胞菌群体感应系统有抑制作用,结果有助于新型抗生素的研究.

英文摘要：

Objective To screen for P.. aeruginosa quorum sensing inhibitors （QSI） from a range of Chinese herbs that are known for treating infections （i.e. Qing Re Jie Du）. Methods The promoters of QS （quorum sensing） genes （lasI, lasR, rhlI and rhlR） fused with luxCDABE reporter were used as the screen system. Both dick diffusion assay and liquid expression profiling were used. The expression of QS related gene clusters in the presence and absence of herbal extracts were monitored. Result The extract of Sculellaria barbara could inhibit QS genes, rhlI, rhlR, lasI and lasR in P. aeruginosa PAO 1, while had no influence on cell viability. Sculellaria barbara extract also repressed swarming and twitching motilities of P. aeruginosa PAO 1. Conclusion Sculellaria barbara extract shows inhibition on quorum-sensing in P. aeruginosa PAO 1. These results suggest new classes of antibiotics may be developed using Chinese herbs.