title: Complete type III secretion system of a mesophilic Aeromonas hydrophila strain.
abstract: We have investigated the existence and genetic organization of a functional type III secretion system (TTSS) in a mesophilic Aeromonas strain by initially using the Aeromonas hydrophila strain AH-3. We report for the first time the complete TTSS DNA sequence of an Aeromonas strain that comprises 35 genes organized in a similar disposition as that in Pseudomonas aeruginosa. Using several gene probes, we also determined the presence of a TTSS in clinical or environmental strains of different Aeromonas species: A. hydrophila, A. veronii, and A. caviae. By using one of the TTSS genes (ascV), we were able to obtain a defined insertion mutant in strain AH-3 (AH-3AscV), which showed reduced toxicity and virulence in comparison with the wild-type strain. Complementation of the mutant strain with a plasmid vector carrying ascV was fully able to restore the wild-type toxicity and virulence.
authors.affiliation: Departamento Microbiología, Facultad Biología, Universidad de Barcelona, Barcelona, Spain.
authors.forename: Silvia
authors.initials: S
authors.lastname: Vilches
authors.forename: Cecilia
authors.initials: C
authors.lastname: Urgell
authors.forename: Susana
authors.initials: S
authors.lastname: Merino
authors.forename: Matilde R
authors.initials: MR
authors.lastname: Chacón
authors.forename: Lara
authors.initials: L
authors.lastname: Soler
authors.forename: Graciela
authors.initials: G
authors.lastname: Castro-Escarpulli
authors.forename: Maria Jose
authors.initials: MJ
authors.lastname: Figueras
authors.forename: Juan M
authors.initials: JM
authors.lastname: Tomás
mesh_terms: D000333:Aeromonas / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity; D016980:Aeromonas hydrophila / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000382:microbiology; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D005810:Multigene Family; D017422:Sequence Analysis, DNA; D014774:Virulence
chemical_list: D001426:Bacterial Proteins