In Pseudomonas aeruginosa,the dynamic activity of type IV pilus(TFP)is essential for various bacterial behaviors.While PilU isconsidered a homolog of the TFP disassembling motor PilT,its specific roles remain unclear.U...In Pseudomonas aeruginosa,the dynamic activity of type IV pilus(TFP)is essential for various bacterial behaviors.While PilU isconsidered a homolog of the TFP disassembling motor PilT,its specific roles remain unclear.Using pilus visualization andsingle-cell tracking techniques,we characterized TFP dynamics and surface behaviors in wild-type andΔpilU mutants.Wefound thatΔpilU cells displayed increased TFP numbers but reduced cell movement and delayed microcolony formation.Interestingly,beyond affecting the twitching motility,ΔpilU cells formed a thick multilayered colony edge on semi-solid sur-faces,slowing colony expansion.Cell-cell collision responses changed from touch-turn dominance in wild type to touch-upright dominance inΔpilU,affecting colony morphology and expansion.Thesefindings expand our understanding of PilU'sphysiological roles and provide potential targets for developing strategies to control P.aeruginosa biofilm formation andvirulence.展开更多
基金Supported by the National Natural ScienceFoundation of China(12374206)to K.Z.National Key R&DProgram of China(2023YFC3402401)to K.Z.+2 种基金National KeyR&D Program of China(2020YFA0906900)to F.J.China,Postdoctoral Science Foundation(2023M740523)to J.Z.Sichuan Provincial People's Hospital Research Fund ofthe Academy(2022B1013)to J.Z。
文摘In Pseudomonas aeruginosa,the dynamic activity of type IV pilus(TFP)is essential for various bacterial behaviors.While PilU isconsidered a homolog of the TFP disassembling motor PilT,its specific roles remain unclear.Using pilus visualization andsingle-cell tracking techniques,we characterized TFP dynamics and surface behaviors in wild-type andΔpilU mutants.Wefound thatΔpilU cells displayed increased TFP numbers but reduced cell movement and delayed microcolony formation.Interestingly,beyond affecting the twitching motility,ΔpilU cells formed a thick multilayered colony edge on semi-solid sur-faces,slowing colony expansion.Cell-cell collision responses changed from touch-turn dominance in wild type to touch-upright dominance inΔpilU,affecting colony morphology and expansion.Thesefindings expand our understanding of PilU'sphysiological roles and provide potential targets for developing strategies to control P.aeruginosa biofilm formation andvirulence.
