A Cloeckaert

..Evidence is provided that Salmonella enterica serovar Agona strains isolated from poultry harbor a similar gene cluster including the newly described floR gene, conferring cross-resistance to chloramphenicol and florfenicol...

..Thus, this PCR assay is able to differentiate Brucella terrestrial isolates from marine mammal isolates and could be applied for diagnostic purposes...

..1 strain. Thus, these Rev.1 bp26 or omp31 deletion mutants are promising vaccine candidates against B. melitensis and B. ovis infections and will be further evaluated in sheep...

..melitensis Rev.1. Therefore, these mutant strains appear interesting vaccine candidates for the future. The other group 3 proteins identified in the genome merit also further investigation related to the development of new vaccines...

..melitensis Rev.1-vaccinated sheep. Weak antibody responses to BP26 in some of the latter sheep suggest that a B. melitensis Rev.1 bp26 gene deletion mutant should be constructed to ensure this differentiation...

..coli and future directions of research with particular attention to the recent development of efflux pump inhibitors as possible means of avoiding the emergence and spread of fluoroquinolone resistance...

..enterica Typhimurium phage types and other S. enterica serovars, the development of specific detection methods, virulence characteristics, and the evolution of multidrug-resistance with regard to the emergence of quinolone resistance...

....

..pinnipediae and B. cetaceae, could be compatible with the classical criteria of host preferentialism and DNA polymorphism at their omp2 locus...

..PCR-restriction fragment length polymorphism (PCR-RFLP) using NciI applied to a large number of Brucella reference and field strains showed that the mutation detected was specific of vaccine strain Rev.1...

..and thus may have been acquired before species differentiation. Some of the species- or biovar-specific markers detected could be used for molecular typing of brucellae in addition to those previously described...

..Thus, the results clearly show that strain RB51 produces low levels of M-like O-antigen...

..The nucleotide sequences of specific DNA fragments detected by IRS-PCR were determined and used to develop PCR identification tests for either B. cetaceae or B. pinnipediae...

..The putative Omp16 and Omp19 homologs in these bacteria showed the same apparent molecular masses as their Brucella counterparts. None of the antilipoprotein MAbs cross-reacted with Y. enterocolitica O:9, E. coli O:157, or S. urbana...

..The isolate carried another class 1 integron containing the aacC5 and aadA7 gene cassettes conferring resistance to gentamicin and streptomycin/spectinomycin, respectively...

..Analysis of the floR gene flanking regions of one of the plasmids showed that they were different from those encountered in S. enterica serovar Typhimurium DT104...

..The most prevalent serovar spreading this resistance was serovar Infantis...

..Immunoblotting performed with sera from either naturally infected or B. melitensis H38 experimentally infected sheep confirmed the importance of the B. melitensis CP28/BP26 protein as diagnostic antigen...

..Sequencing of this DNA fragment will help to identify the missing genes in B. abortus which could possibly be involved in the differences of pathogenicity and host preference seen in Brucella species...

..coli and Haemophilus influenzae Rd, respectively. Sera from naturally infected sheep and sheep experimentally infected with B. melitensis H38 showed antibody reactivity against recombinant CP24...

..8 and 51.2% identity to the dihydrolipoamide succinyltransferase SucB protein from Brucella abortus and Escherichia coli, respectively. Sera from naturally infected sheep showed antibody reactivity against the recombinant SucB protein...

..melitensis infection in mice...

....

..The occurrence of SGI1 in different S. enterica serovars, now including serovar Newport, strengthens the hypothesis of horizontal transfer of SGI1...

..and that the short deletion found in the omp25 gene of B. ovis has important consequences for the expression of surface B-cell epitopes which should be considered for the development of vaccines against B. ovis infection...

..Thus, this study underlines the role of an acrR mutation, in addition to the mutation in gyrA, in the fluoroquinolone and multidrug resistance phenotype of S. Typhimurium mutants, through overexpression of acrAB...

....

..Thus, using EPI together with fluoroquinolones such as Enr may be promising in combination therapy against high-level fluoroquinolone-resistant S. enterica serovar Typhimurium...

....

..Ribotyping (HindIII rDNA restriction patterns) showed that they may represent a separate subgroup (marine type) specifically associated with marine mammals...

..This indicated that at least two independent selection events may have occurred...

..Thus, SGI1 is largely encountered in serovar Agona strains isolated from poultry in Belgium, the most prevalent variant being SGI1-A. SGI1 MDR region undergoes recombinational events resulting in a diversity of MDR gene clusters...

..Thus, this assay accurately differentiates B. ovis from other R Brucella isolates. The latex coagglutination assay can substitute, to advantage, for the current anti-Brucella (R) rabbit monospecific serum...

..Thus, these results showed that the point mutation was responsible, via a lack of binding of the CmeR repressor, for increased expression of the CmeABC efflux pump and consecutive multidrug resistance...

..Some of the identified proteins and their potential specific regulation could be required for the adaptation of B. melitensis to environmental stresses encountered in phagocytic cells and possibly for bacterial virulence...

....

..Thus, S-LPSs of the marine mammal isolates show heterogeneity with regard to their O-PS C epitope content and their average size...

..To evaluate the importance of the inner membrane transporter AcrB and the outer membrane component TolC of this efflux system in the colonization of two multidrug-resistant S. Typhimurium DT104 and one DT204 strain in chicks...

..Of these, the acidic residue D23 seems to participate directly in the affinity pocket involved in phenicol derivative recognition. A third residue, E283 in TMS9, seems to be necessary for correct membrane folding of the transporter...

..063 mg/L). CONCLUSION: The AcrAB-TolC efflux system, together with multiple target gene mutations, including the parC mutation, appear essential to confer high-level fluoroquinolone resistance in S. Typhimurium DT204...

..By IncI1 plasmid subtyping, this plasmid was shown to be genetically related to that found in Escherichia coli isolates from healthy poultry in France...

..Typhimurium into target host cells. Therefore, this role of TolC in the invasion of the intestine in addition to its role in bile salt resistance reinforces the interest of targeting TolC for fighting multidrug-resistant Salmonella...

..Previous studies have shown that SGI1 integrates site-specifically into the S. enterica, Escherichia coli, or Proteus mirabilis chromosome at the 3' end of thdF gene (attB site)...

..Although hooded seal isolates are classified within B. pinnipedialis it was shown in this study that they do not carry this genomic island and this raises the question about their evolutionary history within B. pinnipedialis...

....

....

..The 5-bp target duplication flanking the complex integron suggests that its insertion in ORF S023 was by transposition...

....

..In smooth brucellae, lipopolysaccharide is made of lipid A-core oligosaccharide and N-formylperosamine O-polysaccharide. B. ovis and B. canis (rough species) lack the O-polysaccharide...

..In these conditions, we can ask who is faster: humans who want to eliminate bacterial pathogens or bacteria that continuously evolve to gain new niches...

..Therefore, AcrAB-TolC appears to direct efflux-mediated resistance to quinolones, chloramphenicol-florfenicol, and tetracyclines in multidrug-resistant S. enterica serovar Typhimurium DT104 strains...

..Our data support their current classification into two species, Brucella ceti and B. pinnipedialis, with subgroups in each, but also the possibility of additional species...

..jejuni isolates. Results obtained during ciprofloxacin accumulation studies confirmed that efflux probably plays a minor role in fluoroquinolone resistance of C. jejuni...

..This suggests the involvement of efflux in intrinsic and in acquired low-level of resistance to erythromycin in C. coli...

..ovis infected rams found positive (90%) in the recombinant BP26-I-ELISA indicated that the BP26 protein may be an additional suitable antigen for serological diagnosis of B. ovis infection in rams...

..A previously published assay comprising 16 loci (MLVA-16) that has been shown to be highly relevant and efficient for typing and clustering Brucella strains from animal and human origin was used...

....

..This study was conducted to examine the genetic variation occurring in the cmeB gene encoding the transporter component of the CmeABC efflux pump...

..suis or in other Brucella species and we propose a nomenclature that integrates all of these proteins to facilitate the understanding of future Brucella interspecies study results...

..nov. with the type strain CCM 4915(T) (=BCCN 07-01(T)=CAPM 6434(T)) is proposed...

..In conclusion, the recombinant Omp31 associated or not with B. ovis R-LPS, could be an interesting candidate for a subcellular vaccine against B. ovis infection...

..In conclusion, mutations in ramR appear to play a major role in the upregulation of RamA and AcrAB and, consequently, in the efflux-mediated MDR phenotype of serovar Typhimurium...

..It was concluded that the microarray technique in combination with random primed genomic labeling and 50- or 60-mer oligonucleotides is a powerful tool for the detection of antibiotic resistance genes in bacteria...

..Thus, use of this recombinant fusion protein instead the entire recombinant BP26 could improve the specific serological diagnosis of B. melitensis or B. ovis infection in sheep...

..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...

..We hypothesize that the MDR of SGI1 is subject to recombinational events that lead to the various resistance phenotypes in the Salmonella strains in which it is found...

..melitensis. However, the potential of CP24 for a Brucella diagnostic test based on an in vitro antigen (Ag)-specific IFN-gamma production or DTH test would be worth testing...

..Sequencing showed that SGI1 and variants were integrated at the 3' end of the chromosomal thdF gene as previously described for Salmonella strains...

....

..ovis inside host cells. This aspect, together with the role of Omp25d and Omp22 in the virulence both of B. ovis in rams and of other Brucella species, should be thoroughly evaluated in future studies...

..Emergence of extended-spectrum beta-lactamase-producing S. enterica strains in food animals is a major concern, as such strains could disseminate on a large scale and lead to antibiotic therapy difficulties...

....

..Fluoroquinolone resistance in S. Choleraesuis appears to be the combination effect of multiple mutations in various target genes and overexpression of the Acr AB-TolC efflux pump...

..The data presented highlight the need to develop an alternate method for the eradication of Salmonella spp. from turtle eggs...

..A florfenicol-resistant Pasteurella trehalosi isolate from a calf was investigated for the presence and the location of the gene floR...

....

..This review is intended to provide an update on what is currently known about the genetic basis of antimicrobial resistance in Salmonella...

..CTX-M-2-producing Salmonella with a reduced susceptibility to fluoroquinolones constitutes a major concern, since such strains could disseminate on a large scale and jeopardize classical antibiotic therapy in immunocompromised patients...

..ovis. The DNA polymorphism we have found in this work within the genus Brucella might be involved in the differences in pathogenicity and host preference displayed by the Brucella species...

..Salmonella enterica isolates of six serovars and mutants obtained during determination of mutant prevention concentrations (MPCs) were investigated for mechanisms of decreased susceptibility to fluoroquinolones...

..A multiresistant Aeromonas bestiarum strain, shown to be persistent and spreading in a freshwater stream, was investigated for the presence, location and organization of antimicrobial resistance genes...