Résumé
Objective To investigate the effect of pvdQ(PA2385)gene on Pseudomonas aeruginosa swarming motility.Methods The plasmid pME6032 with pvdQ gene was constructed and identified,then transformed into Pseudomonas aeruginosa PAO1 using the eleetroporation to build pvdQ-overexpression strain.The pME6032-PAO1 strain was constructed with the same method.The cloning plasmid pEX18Gm containing sacB was successfully used to construct unmarked deletion mutant of pvdQ gene and pvdQ mutant strain. Bacteria were inoculated in LB and were cultured overnight.The clones were measured for the diameter of the swarming zone.The statistical analysis was done using one-factor ANOVA.Results Strains of pvdQ-overexpression and pvdQ-mutant were successfully constructed and confirmed by polymerase chain reaction(PCR).The four strains were compared for the swarming motility by changes in diameter:PAO1(20.52±1.80)mm,pME6032-PAO1 strain(19.39±2.10)mm,pvdQ-overexpression strain(51.20±2.16)mm,pvdQ-mutant strain(3.30±0.55)mm.The diameter of pME6032-PAO1 strain was not significantly different from that of wild strain PAO1(t=-0.1493,P>0.05).However,the diameter of pvdQ(Q-mutant strain was significantly shorter than that of wild strain PAO1(t=2.8525,P<0.05).while the diameter of pvdQ-overexpression strain was longer than that of the wild strain PAO1(t=1.4230,P<0.05).Conclusions pvdQ gene may be involved in regulating the swarming motility of Pseudomonas aeruginosa,which can promote Pseudomonas aeruginosa swarming motility.
Résumé
Objective To investigate whether Pseudomonas aeruginosa pvdQ( PA2385 ) gene reveals altered antibiotic susceptibility under swarming conditions. Methods The plasmid pME6032 with pvdQ gene was constructed and identified, then transformed into Pseudomonas aeruginosa PAO1 by the electroporation, building pvdQ overexpression strain. Using the same method building pME6032-PAO1 strain.Bacteria were inoculated in LB overnight , measuring the colony diameter of the swarming zone . Results Strains of pvdQ overexpression was successfully constructed by real-time PCR. Comparison of two strains of the swarming motility of change in diameter: The result showed that PAO1 and pvdQ overexpression strains can both improve the antibiotics resistance. Swarmer cells of pvdQ overexpression strain exhibited a 2- to 4-fold increase in antibiotic resistance toward ceftazidime,ciprofloxacin, meropenem and polymyxin B compared to PAO1 on BM2-swarming agar plates. Conclusion pvdQ gene played an important role in elevating the antibiotics resistance, which through prarticipated in the swarmer cell differentiation.