bearer of at some time only_in_taxon Brucella virulence factor disposition Brucella melitensis biovar Abortus 2308 BAB2_0067 protein type IV secretion system protein VirB2 KO: K03197 type IV secretion system protein VirB2 NCBIProteinAccess:YP_418312.1 This protein is a Brucella virulence factor. MUTATION: The Brucella abortus virB operon, encoding a type IV secretion system (T4SS), is required for intracellular replication and persistent infection in the mouse model. The products of the first two genes of the virB operon, virB1 and virB2, are predicted to be localized at the bacterial surface. Both mutants were shown to be nonpolar, as demonstrated by their ability to express the downstream gene virB5 during stationary phase of growth in vitro. Both VirB1 and VirB2 were essential for intracellular replication in J774 macrophages. The nonpolar virB2 mutant was unable to cause persistent infection in the mouse model, demonstrating the essential role of VirB2 in the function of the T4SS apparatus during infection [Ref6539:den et al., 2004]. Polar mutations in the virB1 to virB2 intergenic region or in virB2 reduced the detection of VirB5 to a greater extent than they did that of VirB12. A virB1 mutation also eliminates the transcription of virB12 in B suis [Ref6470:Sun et al., 2005]. Molecule Role Annotation: MUTATION: The Brucella abortus virB operon, encoding a type IV secretion system (T4SS), is required for intracellular replication and persistent infection in the mouse model. The products of the first two genes of the virB operon, virB1 and virB2, are predicted to be localized at the bacterial surface. Both mutants were shown to be nonpolar, as demonstrated by their ability to express the downstream gene virB5 during stationary phase of growth in vitro. Both VirB1 and VirB2 were essential for intracellular replication in J774 macrophages. The nonpolar virB2 mutant was unable to cause persistent infection in the mouse model, demonstrating the essential role of VirB2 in the function of the T4SS apparatus during infection [Ref6539:den et al., 2004]. Polar mutations in the virB1 to virB2 intergenic region or in virB2 reduced the detection of VirB5 to a greater extent than they did that of VirB12. A virB1 mutation also eliminates the transcription of virB12 in B suis [Ref6470:Sun et al., 2005]. LocusTag: BAB2_0067 UniProtKB: PR:Q2YIT6 NCBIGene: 3827981 NCBIProteinGI: 83269021 Gene name: virB2 PMID: 15322008, 16113325