4/10/2023 0 Comments Pasteurellose caprineMultilocus sequence typing (MLST) analysis using nine different loci also placed the two isolates separately from other brucellae. In comparative multilocus VNTR (variable-number tandem-repeat) analysis (MLVA) with 296 different genotypes, the two isolates grouped together, but formed a separate cluster within the genus Brucella. Both strains harboured five to six copies of the insertion element IS711, displaying a unique banding pattern as determined by Southern blotting. Analysis of the bp26 gene downstream region identified strains CCM 4915(T) and CCM 4916 as Brucella of terrestrial origin. Whereas omp2a was identical to omp2a of brucellae from certain pinniped marine mammals, omp2b clustered with omp2b of terrestrial brucellae. The omp2a and omp2b genes of isolates CCM 4915(T) and CCM 4916 were indistinguishable. Biochemical profiling revealed a high degree of enzyme activity and metabolic capabilities not observed in other Brucella species. Both strains reacted equally with Brucella M-monospecific antiserum and were lysed by the bacteriophages Tb, Wb, F1 and F25. Affiliation to Brucella was confirmed by DNA-DNA hybridization studies. On the basis of 16S rRNA (rrs) and recA gene sequence similarities, both isolates were allocated to the genus Brucella. Two Gram-negative, non-motile, non-spore-forming, coccoid bacteria (strains CCM 4915(T) and CCM 4916), isolated from clinical specimens of the common vole Microtus arvalis during an epizootic in the Czech Republic in 2001, were subjected to a polyphasic taxonomic study. is NCTC 12891T (=BCCN 94-74T) and the type strain of Brucella pinnipedialis sp. are proposed for the isolates from cetaceans and seals, respectively. The 28 strains could be further separated into two groups with cetaceans and seals as their respective preferred hosts on the basis of molecular methods and on differences in the metabolism of l-arabinose, d-galactose and d-xylose. Twenty-eight European isolates of the genus Brucella from marine mammals were distinguished from the six recognized species by their pattern of utilization of eleven substrates in oxidative metabolism tests and phage lysis. Their placement in the genus Brucella has been supported by the following characteristics: they are aerobic, non-motile and catalase-positive, do not produce acid from carbohydrates and have a DNA-DNA relatedness value of >77% with the six established members of the genus. Small Gram-negative cocco-bacilli resembling Brucella strains have been reported from marine mammals since the mid-1990s. Because of its unexpected isolation, the name Brucella inopinata with the type strain BO1(T) (=BCCN 09-01(T)=CPAM 6436(T)) is proposed. From the phenotypic and molecular analysis it became evident that strain BO1( T) was clearly different from all other Brucella species, and therefore represents a novel species within the genus Brucella. Using the Brucella species-specific multiplex PCR assay, strain BO1(T) displayed a unique banding pattern not observed in other Brucella species. The recA gene sequence of strain BO1(T) differed in seven nucleotides from the Brucella recA consensus sequence. Comparative omp2a and omp2b gene sequence analysis revealed the most divergent omp2 sequences identified to date for a Brucella strain. In multilocus VNTR (variable-number tandem-repeat) analysis, strain BO1(T) showed a very distinctive profile and clustered with the other 'exotic' Brucella strains, including strains isolated from marine mammals, and Brucella microti, Brucella suis biovar 5 and Brucella neotomae. Biochemical profiling revealed a high degree of enzymic activity and metabolic capabilities. Incomplete lysis was detected with bacteriophages Tb (Tbilisi), F1 and F25. Strain BO1(T) reacted with Brucella M-monospecific antiserum. Strain BO1(T) harboured four to five copies of the Brucella-specific insertion element IS 711, displaying a unique banding pattern, and exhibited a unique 16S rRNA gene sequence and also grouped separately in multilocus sequence typing analysis. Affiliation of strain BO1(T) to the genus Brucella was confirmed by means of polyamine pattern, polar lipid profile, fatty acid profile, quinone system, DNA-DNA hybridization studies and by insertion sequence 711 (IS711)-specific PCR. A Gram-negative, non-motile, non-spore-forming coccoid bacterium (strain BO1(T)) was isolated recently from a breast implant infection of a 71-year-old female patient with clinical signs of brucellosis.
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