An oligonucleotide microarray prototype was designed and is being evaluated permitting rapid identification of some pathogenic bacteria that may cause abortion in animals such as Brucella sp, Campylobacter fetus subsp fetus, Campylobacter jejuni subsp jejuni, Campylobacter jejuni subsp doyle, Campylobacter coli, Listeria monocytogenes, Listeria ivanovii, Salmonella enterica ssp enterica serovar Abortusovis, Salmonella enterica ssp enterica serovar Dublin, bacteria that may elicit serological cross-reactivity to Brucella sp in an infectious process as Vibrio cholerae, Yersinia enterocolitica O9, Escherichia coli O157:H7 and phylogenetically related bacteria of the order Rhizobiales of the Alphaproteobacteria; Ochrobactrum anthropi, Mycoplana dimorpha, Ensifer melliloti, Phyllobacterium myrsinacearum, Rhizobium radiobacter and Rhizobium leguminosarum were also included in the study. The microarray uses oligonucleotide sequences that are species specific to the organisms being investigated, it also contains sequences for virulence genes found in Brucella sp and reported in the literature. The microarray was designed and is being evaluated with ATCC/NCTC/DSMZ reference strains.
Preliminary hybridization results were analyzed with clustering software, each organism tested was identified by distinct patterns able to reveal the presence or absence of the selected sequences. All of the zoonotic agents of abortion were correctly classified according to the presence of their species specific genes. Previously identified virulence factors of Brucella sp were present to some degree in all of the different Brucella sp tested and most were absent in all other zoonotic agents of abortion. Preliminary results confirmed microarray hybridization as a powerful tool, which allows rapid identification of the organisms being tested.