title: Outer membrane lipoprotein VacJ is required for the membrane integrity, serum resistance and biofilm formation of Actinobacillus pleuropneumoniae.
abstract: The outer membrane proteins of Actinobacillus pleuropneumoniae are mediators of infection, acting as targets for the host's defense system. The outer membrane lipoprotein VacJ is involved in serum resistance and intercellular spreading in several pathogenic bacteria. To investigate the role of VacJ in the pathogenicity of Actinobacillus pleuropneumoniae, the vacJ gene-deletion mutant MD12 ΔvacJ was constructed. The increased susceptibility to KCl, SDS plus EDTA, and several antibiotics in the MD12ΔvacJ mutant suggested that the stability of the outer membrane was impaired as a result of the mutation in the vacJ gene. The increased NPN fluorescence and significant cellular morphological variation in the MD12ΔvacJ mutant further demonstrated the crucial role of the VacJ lipoprotein in maintaining the outer membrane integrity of A. pleuropneumoniae. In addition, the MD12ΔvacJ mutant exhibited decreased survival from the serum and complement killing compared to the wild-type strain. Interestingly, the MD12ΔvacJ mutant showed reduced biofilm formation compared to the wild-type strain. To our knowledge, this is the first description of the VacJ lipoprotein contributing to bacterial biofilm formation. The data presented in this study illustrate the important role of the VacJ lipoprotein in the maintenance of cellular integrity, serum resistance, and biofilm formation in A. pleuropneumoniae.
authors.affiliation: State Key Laboratory of Veterinary Biotechnology, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 15001, People's Republic of China.
authors.forename: Fang
authors.initials: F
authors.lastname: Xie
authors.affiliation: State Key Laboratory of Veterinary Biotechnology, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 15001, People's Republic of China.
authors.forename: Gang
authors.initials: G
authors.lastname: Li
authors.affiliation: State Key Laboratory of Veterinary Biotechnology, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 15001, People's Republic of China.
authors.forename: Wanjiang
authors.initials: W
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Veterinary Biotechnology, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 15001, People's Republic of China.
authors.forename: Yanhe
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Veterinary Biotechnology, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 15001, People's Republic of China.
authors.forename: Long
authors.initials: L
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Veterinary Biotechnology, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 15001, People's Republic of China.
authors.forename: Shuanghong
authors.initials: S
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Veterinary Biotechnology, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 15001, People's Republic of China.
authors.forename: Siguo
authors.initials: S
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Veterinary Biotechnology, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 15001, People's Republic of China. Electronic address: chunlai.w@hvri.ac.cn.
authors.forename: Chunlai
authors.initials: C
authors.lastname: Wang
mesh_terms: D016977:Actinobacillus pleuropneumoniae / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology*; D000595:Amino Acid Sequence; D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D018441:Biofilms; D002462:Cell Membrane / Q000235:genetics; D017353:Gene Deletion; D050296:Microbial Viability / Q000235:genetics; D046529:Microscopy, Electron, Transmission; D064587:Osmoregulation / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D044967:Serum / Q000382:microbiology; D013552:Swine
chemical_list: D000890:Anti-Infective Agents; D001425:Bacterial Outer Membrane Proteins; D011994:Recombinant Proteins
keywords: Outer membrane integrity; VacJ lipoprotein