Furthermore, a screening of the Micronaut-IDS database (Merlin Diagnostika) which is a widely used rapid identification system for Gram-negative and Gram-positive bacteria clearly discriminated brucellae from other bacterial taxa on the basis of four enzymatic reactions i.e. HP, Pyr-βNA (Pyr), urease, and NTA [Additional file 8, only clinically
relevant bacteria are shown]. Table 1 Specificity of the Brucella specific eFT-508 Micronaut™ microtiter plate. Brucella spp. Specificity in % Species Biovars Biovar differentiation Species differentiation 1 0 2 75 3 90 B. abortus 4 100 100 5 100 6 0 7 100 9 0 1 19 100 B. melitensis 2 89 3 64 1 100 74 100 99 2 100 B. suis 3 100 4 100 5 100 B. ovis 100 B. canis 60 B. neotomae 100 B. ceti 100 B. pinnipedialis 100 B. microti 100 B. inopinata 100 Specificity of the Micronaut™ system to differentiate Brucella species and biovars. SC79 nmr The biotyping
results were independent of the host and the geographic origin of Brucella isolates. Discussion Classical phenotyping and PF-6463922 in vivo metabolic markers of Brucella spp Although Brucella is a monophyletic genus, apparent differences between its species do exist e.g. host specificity and pathogenicity. Nowadays, Brucella species and biovars are distinguished by a limited number of microbiological tests measuring quantitative or qualitative differences of dye bacteriostasis, hydrogen sulfide production, urea hydrolysis, carbon dioxide requirement, bacteriophage sensitivity and agglutinin absorption. For at least half a century these microbiological procedures have not changed, although various new Brucella species showing
variable phenotypic traits have been detected and new diagnostic methods have been developed. Neither the classical biochemical tests nor antigenic properties and phage-sensitivity can be considered a reliable guide to the identification of Brucella species. Contradictory results were often reported [14]. However, variations in H2S production, CO2 requirement, a change in dye tolerance or atypical surface antigens i.e. inconsistent A and M antigens usually do not affect the oxidative metabolic pattern of a strain [15, 16]. Metabolic Forskolin activities have proven to be stable parameters allowing unambiguous species identification, particularly in strains which show conflicting identities by conventional determinative methods [14, 17–19]. In addition, differing metabolism may help to describe new species [6, 9, 20]. In our series, two strains isolated from foxes in Austria (strain no. 110 and 111) which displayed an atypical metabolic pattern could be identified. Oxidative metabolic profiles remain qualitatively stable for long periods of time and usually show no change in characteristic patterns after in vivo and in vitro passages [21].