title: [RmlA gene deletion affects biofilm formation by avian pathogenic Escherichia coli].
abstract: OBJECTIVE
  To characterize rmlA gene inavian pathogenic Escherichia coli (APEC).
  
  
  METHODS
  We constructed the rmlA mutant of APEC by the Red recombination system. Then we analyzed the differences of growth, movement and biofilm formation between mutant strain and wild strain. We compared the differences of virulence gene transcription between mutant strain and wild strain by real-time PCR.
  
  
  RESULTS
  The rmlA mutant did not affect the growth and motility of APEC, but enhanced the biofilm formation significantly. In addition, the transcription level of some virulence genes in rmlA mutant showed that the luxS , irp2 were raised 2 and 1.6 times respectively, but decreased the iucD and fyuA by 25 times compared to the wild strain.
  
  
  CONCLUSIONS
  These data indicate that the rmlA gene could strengthen the ability of APEC biofilm formation, and affect the transcription level of some virulence genes, but not the growth and motility.
authors.affiliation: Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Han
authors.affiliation: Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China.
authors.forename: Xiangan
authors.initials: X
authors.lastname: Han
authors.affiliation: Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Bai
authors.affiliation: Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China.
authors.forename: Shaohui
authors.initials: S
authors.lastname: Wang
authors.affiliation: Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China.
authors.forename: Qingmei
authors.initials: Q
authors.lastname: Meng
authors.affiliation: Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China.
authors.forename: Chan
authors.initials: C
authors.lastname: Ding
authors.affiliation: Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China.
authors.forename: Shengqing
authors.initials: S
authors.lastname: Yu
mesh_terms: D000818:Animals; D018441:Biofilms; D004372:Ducks; D004926:Escherichia coli / Q000235:genetics / Q000502:physiology*; D004927:Escherichia coli Infections / Q000382:microbiology / Q000662:veterinary*; D017353:Gene Deletion; D009713:Nucleotidyltransferases / Q000235:genetics* / Q000378:metabolism; D011201:Poultry Diseases / Q000382:microbiology*; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D037521:Virulence Factors; D009713:Nucleotidyltransferases; C020587:glucose-1-phosphate thymidylyltransferase