title: Actinobacillus pleuropneumoniae does not require urease activity to produce acute swine pleuropneumonia.
abstract: The role in virulence of Actinobacillus pleuropneumoniae urease activity was investigated. A urease-negative mutant was isolated following transposon mutagenesis with a mini-Tn10 derivative. Both the parent strain and the urease-negative mutant exhibited identical LD50 values in a murine infection model. Pig challenge confirmed that the urease-negative mutant was fully virulent, since experimental inoculation with 5 x 10(7) colony forming units resulted in an acute disease indistinguishable from that produced by the wild-type strain at the same dose. Our results demonstrate that urease activity is not required for the development of acute pleuropneumonia.
authors.affiliation: Departamento de Patologia Animal-Sanidad Animal, Facultad de Veterinaria, Universidad de León, Spain. dsartc@isidoro.unileon.es
authors.forename: R I
authors.initials: RI
authors.lastname: Tascón Cabrero
authors.forename: J A
authors.initials: JA
authors.lastname: Vázquez-Boland
authors.forename: C B
authors.initials: CB
authors.lastname: Gutiérrez
authors.forename: J I
authors.initials: JI
authors.lastname: Rodríguez-Barbosa
authors.forename: E F
authors.initials: EF
authors.lastname: Rodríguez-Ferri
mesh_terms: D016977:Actinobacillus pleuropneumoniae / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity; D000818:Animals; D001426:Bacterial Proteins / Q000378:metabolism; D015139:Blotting, Southern; D004251:DNA Transposable Elements; D004269:DNA, Bacterial / Q000032:analysis; D005260:Female; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D016296:Mutagenesis; D011001:Pleuropneumonia / Q000382:microbiology*; D013552:Swine; D013553:Swine Diseases / Q000382:microbiology*; D014510:Urease / Q000235:genetics / Q000378:metabolism*; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D014510:Urease