bearer of at some time only_in_taxon Brucella virulence factor disposition Brucella suis 1330 omp25 protein outer-membrane protein Omp25 NCBIProteinGI: 23501588 Molecule Role Annotation: SUBCELLULAR LOCATION: Outer membrane(Swiss-Prot: Q45689). SIMILARITY: Belongs to the omp25/ropB family(Swiss-Prot: Q45689). MUTATION: In contrast to WT B suis or Deltaomp31 B suis, Deltaomp25 B suis induced TNF-alpha production when phagocytosed by human macrophages. So Omp25 of B suis is involved in the negative regulation of TNF-alpha production upon infection of human macrophages [Ref6492:Jubier-Maurin et al., 2001]. To determine the role of Omp25 in virulence, mutants were created with Brucella abortus (BA25), Brucella melitensis (BM25), and Brucella ovis (BO25) which contain disruptions in the omp25 gene (Deltaomp25 mutants). BALBc mice infected with B abortus BA25 or B melitensis BM25 showed a significant decrease in mean CFUspleen at 18 and 4 weeks post-infection, respectively, when compared to the virulent parental strain. Mice infected with B ovis BO25 had significantly lower mean CFUspleen counts from 1 to 8 weeks post-infection, at which point the mutant was cleared from the spleens. Murine vaccination with either BM25 or the current caprine vaccine B melitensis strain Rev.1 resulted in more than a 2log (10) reduction in bacterial load following challenge with virulent B melitensis. Vaccination of mice with the B ovis mutant resulted in clearance of the challenge strain and provided 2.5log (10) greater protection against virulent B ovis than vaccine strain Rev.1. Based on these data, the B melitensis and B ovis Deltaomp25 mutants are interesting vaccine candidates that are currently under study in our laboratory for their safety and efficacy in small ruminants [Ref6492:Jubier-Maurin et al., 2001]. Although they are slightly attenuated, B abortus omp25 and omp22 mutants do not show the high level of attenuation and sensitivity to bactericidal peptides displayed by the bvrS and bvrR mutants [Ref6492:Jubier-Maurin et al., 2001]. B abortus mutants carrying Omp25 deletions do not show enrichment of underacylated LPS [Ref6492:Jubier-Maurin et al., 2001]. Brucella spp. omp25 deletion mutants are attenuated in mice, cattle and goats, showing the involvement of Brucella spp. Omp25 in virulence [Ref6492:Jubier-Maurin et al., 2001]. NCBIGene: 1166364 LocusTag: BR0701 NCBIProteinAccess:NP_697715.1 Gene name: omp25 UniProtKB: PR:Q45689 PMID: 11447156 This protein is a Brucella virulence factor. SUBCELLULAR LOCATION: Outer membrane(Swiss-Prot: Q45689). SIMILARITY: Belongs to the omp25/ropB family(Swiss-Prot: Q45689). MUTATION: In contrast to WT B suis or Deltaomp31 B suis, Deltaomp25 B suis induced TNF-alpha production when phagocytosed by human macrophages. So Omp25 of B suis is involved in the negative regulation of TNF-alpha production upon infection of human macrophages [Ref6492:Jubier-Maurin et al., 2001]. To determine the role of Omp25 in virulence, mutants were created with Brucella abortus (BA25), Brucella melitensis (BM25), and Brucella ovis (BO25) which contain disruptions in the omp25 gene (Deltaomp25 mutants). BALBc mice infected with B abortus BA25 or B melitensis BM25 showed a significant decrease in mean CFUspleen at 18 and 4 weeks post-infection, respectively, when compared to the virulent parental strain. Mice infected with B ovis BO25 had significantly lower mean CFUspleen counts from 1 to 8 weeks post-infection, at which point the mutant was cleared from the spleens. Murine vaccination with either BM25 or the current caprine vaccine B melitensis strain Rev.1 resulted in more than a 2log (10) reduction in bacterial load following challenge with virulent B melitensis. Vaccination of mice with the B ovis mutant resulted in clearance of the challenge strain and provided 2.5log (10) greater protection against virulent B ovis than vaccine strain Rev.1. Based on these data, the B melitensis and B ovis Deltaomp25 mutants are interesting vaccine candidates that are currently under study in our laboratory for their safety and efficacy in small ruminants [Ref6492:Jubier-Maurin et al., 2001]. Although they are slightly attenuated, B abortus omp25 and omp22 mutants do not show the high level of attenuation and sensitivity to bactericidal peptides displayed by the bvrS and bvrR mutants [Ref6492:Jubier-Maurin et al., 2001]. B abortus mutants carrying Omp25 deletions do not show enrichment of underacylated LPS [Ref6492:Jubier-Maurin et al., 2001]. Brucella spp. omp25 deletion mutants are attenuated in mice, cattle and goats, showing the involvement of Brucella spp. Omp25 in virulence [Ref6492:Jubier-Maurin et al., 2001].