title: Investigation of TbfA in Riemerella anatipestifer using plasmid-based methods for gene over-expression and knockdown.
abstract: Riemerella anatipestifer is a duck pathogen that has caused serious economic losses to the duck industry worldwide. Despite this, there are few reported studies of the physiological and pathogenic mechanisms of Riemerella anatipestifer infection. In previous study, we have shown that TonB1 and TonB2 were involved in hemin uptake. TonB family protein (TbfA) was not investigated, since knockout of this gene was not successful at that time. Here, we used a plasmid based gene over-expression and knockdown to investigate its function. First, we constructed three Escherichia-Riemerella anatipestifer shuttle vectors containing three different native Riemerella anatipestifer promoters. The shuttle plasmids were introduced into Riemerella anatipestifer ATCC11845 by conjugation at an efficiency of 5 × 10-5antibiotic-resistant transconjugants per recipient cell. Based on the high-expression shuttle vector pLMF03, a method for gene knockdown was established. Knockdown of TbfA in Riemerella anatipestifer ATCC11845 decreased the organism's growth ability in TSB medium but did not affect its hemin utilization. In contrast, over-expression of TbfA in Riemerella anatipestifer ATCC11845ΔtonB1ΔtonB2. Significantly promoted the organism's growth in TSB medium but significantly inhibited its hemin utilization. Collectively, these findings suggest that TbfA is not involved in hemin utilization by Riemerella anatipestifer.
authors.affiliation: Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, P. R. China.
authors.forename: MaFeng
authors.initials: M
authors.lastname: Liu
authors.affiliation: Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, P. R. China.
authors.forename: MengYi
authors.initials: M
authors.lastname: Wang
authors.affiliation: Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, P. R. China.
authors.forename: DeKang
authors.initials: D
authors.lastname: Zhu
authors.affiliation: Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, P. R. China.
authors.forename: MingShu
authors.initials: M
authors.lastname: Wang
authors.affiliation: Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, P. R. China.
authors.forename: RenYong
authors.initials: R
authors.lastname: Jia
authors.affiliation: Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, P. R. China.
authors.forename: Shun
authors.initials: S
authors.lastname: Chen
authors.affiliation: Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, P. R. China.
authors.forename: KunFeng
authors.initials: K
authors.lastname: Sun
authors.affiliation: Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, P. R. China.
authors.forename: Qiao
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, P. R. China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, P. R. China.
authors.forename: XiaoYue
authors.initials: X
authors.lastname: Chen
authors.affiliation: Unité des Infections Bactériennes Invasives, Département Infection et Epidémiologie, Institut Pasteur, Paris, France.
authors.forename: Francis
authors.initials: F
authors.lastname: Biville
authors.affiliation: Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Avian Disease Research Center, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, Sichuan 611130, P.R. China.|Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, P. R. China.
authors.forename: AnChun
authors.initials: A
authors.lastname: Cheng
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D055785:Gene Knockdown Techniques; D006427:Hemin / Q000235:genetics / Q000378:metabolism*; D010957:Plasmids / Q000235:genetics; D060494:Riemerella / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D006427:Hemin