Pseudomonas aeruginosa pvdQ gene prevents Caco-2 cells from obstruction of quorum-sensing signal.

Quorum sensing (QS) system plays an important role in bacterial pathopoiesis of incurable Pseudomonas aeruginosa infection, which strongly warrants new strategies for absence of curative treatment to date. Latest investigations show that pvdQ gene of P. aeruginosa can attenuate the pathopoiesis of the bacteria by encoding acylase enzyme and hydrolyze N-(3-oxododecanoyl)-Homoserine Lactone (3O-oxo-C(12)-HSL), the key signal molecule of QS system. This study tries to resist the pathogenicity of P. aeruginosa by transfecting human intestinal epithelial Caco-2 cells with pvdQ gene. We found that 3O-oxo-C(12)-HSL was decreased in the supernatant of cells transfected with pvdQ gene. Moreover, the result of flow cytometry showed that the 3O-oxo-C(12)-HSL evoked apoptosis rate of Caco-2 cells was inhibited when the cells were transfected with pvdQ gene. In contrast, the control result displayed increased Caco-2 cells' apoptosis rate after stimulation of 3O-oxo-C(12)-HSL without protection of pvdQ gene. In conclusion, we successfully protect mammalian cells Caco-2 from injure of QS signal molecule 3O-oxo-C(12)-HSL through imputing pvdQ gene, which may suggest a new therapeutic strategy for P. aeruginosa infection.