[ Objective] To prepare recombinant type 1 pilus vaccine of avian Escherichia coil and to detect its immunogenicity in chickens. [Meth- od] The type 1 pilus was respectively isolated from the recombinant bacteria CZYR...[ Objective] To prepare recombinant type 1 pilus vaccine of avian Escherichia coil and to detect its immunogenicity in chickens. [Meth- od] The type 1 pilus was respectively isolated from the recombinant bacteria CZYR10 strain and wild avian Eschedchia co/i YR（ O18 ） strain and used to prepare oil-emulsified vaccine. The immunogenicity of the developed vaccine was detected in chickens using the challenge test. [ Result] The recombinant type 1 pilus protein had immunoprotective efficacy. The recombinant type 1 pilus protein had weaker protective efficacy than the isolated type 1 pilus protein, but the difference was not significant. [ Conclusion] The study provides a reference for immunization and control of chicken colibacillosis.展开更多
Lysobacter enzymogenes OH11 is a non-flagellated,ubiquitous soil bacterium with broad-spectrum antifungal activities.Although lacking flagella,it employs another type of motile behavior,known as twitching motility tha...Lysobacter enzymogenes OH11 is a non-flagellated,ubiquitous soil bacterium with broad-spectrum antifungal activities.Although lacking flagella,it employs another type of motile behavior,known as twitching motility that is powered by type IV pilus(T4P)to move towards neighboring crop fungal pathogens to kill them as food.At present,little is known about how this non-flagellated bacterium controls twitching motility that is crucial for its predatory lifestyle.Herein,we present a report on how a non-canonical PilZ domain,PilZ_(Le3639),controls such motility in the non-flagellated L.enzymogenes;it failed to bind with c-di-GMP but seemed to be required for twitching motility.Using bacterial two-hybrid and pull-down approaches,we identified PilB_(Le0708),one of the PilZ_(Le3639)-binding proteins that are essential for the bacterial twitching motility,could serve as an ATPase to supply energy for T4P extension.Through site-mutagenesis approaches,we identified one essential residue of PilZ_(Le3639) that is required for its binding affinity with PilB_(Le0708) and its regulatory function.Besides,two critical residues within the ATPase catalytic domains of PilB_(Le0708) were detected to be essential for regulating twitching behavior but not involved in binding with PilZ_(Le3639).Overall,we illustrated that the PilZ-PilB complex formation is indispensable for twitching motility in a non-flagellated bacterium.展开更多
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funded by the Natural Science Foundation of Jiangsu Province ( BK2008059)
文摘[ Objective] To prepare recombinant type 1 pilus vaccine of avian Escherichia coil and to detect its immunogenicity in chickens. [Meth- od] The type 1 pilus was respectively isolated from the recombinant bacteria CZYR10 strain and wild avian Eschedchia co/i YR（ O18 ） strain and used to prepare oil-emulsified vaccine. The immunogenicity of the developed vaccine was detected in chickens using the challenge test. [ Result] The recombinant type 1 pilus protein had immunoprotective efficacy. The recombinant type 1 pilus protein had weaker protective efficacy than the isolated type 1 pilus protein, but the difference was not significant. [ Conclusion] The study provides a reference for immunization and control of chicken colibacillosis.
基金supported by the Natural Science Foundation of Jiangsu Province(BK20190026,BK20181325)the National Natural Science Foundation of China(31872016)+1 种基金the Fundamental Research Funds for the Central Universities(KJJQ202001,KYT201805,KYTZ201403 and KYT202001)Jiangsu Agricultural Sciences and Technology Innovation Fund[CX(18)1003]and Innovation Team Program for Jiangsu Universities(2017).
文摘Lysobacter enzymogenes OH11 is a non-flagellated,ubiquitous soil bacterium with broad-spectrum antifungal activities.Although lacking flagella,it employs another type of motile behavior,known as twitching motility that is powered by type IV pilus(T4P)to move towards neighboring crop fungal pathogens to kill them as food.At present,little is known about how this non-flagellated bacterium controls twitching motility that is crucial for its predatory lifestyle.Herein,we present a report on how a non-canonical PilZ domain,PilZ_(Le3639),controls such motility in the non-flagellated L.enzymogenes;it failed to bind with c-di-GMP but seemed to be required for twitching motility.Using bacterial two-hybrid and pull-down approaches,we identified PilB_(Le0708),one of the PilZ_(Le3639)-binding proteins that are essential for the bacterial twitching motility,could serve as an ATPase to supply energy for T4P extension.Through site-mutagenesis approaches,we identified one essential residue of PilZ_(Le3639) that is required for its binding affinity with PilB_(Le0708) and its regulatory function.Besides,two critical residues within the ATPase catalytic domains of PilB_(Le0708) were detected to be essential for regulating twitching behavior but not involved in binding with PilZ_(Le3639).Overall,we illustrated that the PilZ-PilB complex formation is indispensable for twitching motility in a non-flagellated bacterium.
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.
