title: Evaluation of Gram-negative bacterial infection by a stable and conjugative bioluminescence plasmid in a mouse model.
abstract: BACKGROUND
  The green fluorescence protein (GFP)-associated fluorescence method and the luciferase-associated bioluminescence method are the two major methods for IVIS imaging system to investigate the bacterial infection in animal models. The aim of this study was to evaluate the infection route of Gram-negative bacteria carrying a stable and broad range of conjugative bioluminescence plasmid pSE-Lux1 in a mouse model.
  
  
  RESULTS
  Both encapsulated and non-encapsulated Gram-negative bacteria were used as hosts to evaluate conjugation efficiency and plasmid stability of pSE-Lux1, a recombinant of pSE34 and luxABCDE operon. The plasmid conjugation efficiencies of pSE-Lux1 ranged from 10⁻³ to 10⁻⁷ in various Gram-negative bacteria. Plasmid pSE-Lux1 maintained in Escherichia coli, Klebsiella pneumoniae, and Salmonella enterica serovars Choleraesues (abbreviated S. Choleraesuis) and Typhimurium (S. Typhimurium), than in Acinetobacter baumannii and Serratia marcescens, was shown to be of better stability for at least four days. To investigate systemic bacterial infections, K. pneumoniae strain CG354 was intravenously injected, and then was clearly observed to be non-pathogenic to Balb/c mice for a long-term bioluminescence monitoring for 6 days. For examining dynamic distributions of gastrointestinal tract infection, the invasion protein SipB-deficient mutant OU5045△sipB and OU5046△sipB of S. serovar Typhimurium constructed in this study, compared to wild-type strain OU5045 and its virulence plasmid-less strain OU5046, were of less virulence to mice.
  
  
  CONCLUSIONS
  This is the first study to evaluate the conjugative and stable bioluminescence vehicle system of pSE-Lux1 in a wide range of Gram-negative bacteria, a system that can provide a useful reporter approach to trace systemic and gastrointestinal bacterial infections in a mouse model.
authors.forename: Yao-Kuang
authors.initials: YK
authors.lastname: Huang
authors.forename: Chishih
authors.initials: C
authors.lastname: Chu
authors.forename: Chih-Hsiung
authors.initials: CH
authors.lastname: Wu
authors.affiliation: Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan. dinoschen@adm.cgmh.org.tw.
authors.forename: Chyi-Liang
authors.initials: CL
authors.lastname: Chen
authors.forename: Cheng-Hsun
authors.initials: CH
authors.lastname: Chiu
mesh_terms: D000818:Animals; D006090:Gram-Negative Bacteria / Q000235:genetics / Q000378:metabolism; D016905:Gram-Negative Bacterial Infections / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D049452:Green Fluorescent Proteins / Q000096:biosynthesis / Q000235:genetics; D008163:Luminescent Measurements; D051379:Mice; D008807:Mice, Inbred BALB C; D057054:Molecular Imaging; D010957:Plasmids
chemical_list: D049452:Green Fluorescent Proteins