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Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 2/15/2006 Publication Date: 8/13/2006 Citation: Liu, Y., Fratamico, P.M. 2006. Escherichia coli o antigen typing using dna microarrays. {Abstract}. International Association of Food Protection. P3-54. Interpretive Summary: Technical Abstract: DNA microarrays were developed for rapid identification of different serogroups of Escherichia coli in a single platform. Oligonucleotides, as well as PCR products from genes in the O-antigen gene clusters of E. coli serogroups O7, O104, O111, and O157 were spotted onto glass slides. This was followed by hybridization with labeled long PCR products of the entire O antigen gene clusters of these serogroups. Results demonstrated that microarrays consisting of either oligonucleotides or PCR products generated specific signals for each serogroup. In related studies, the O antigen gene clusters of E. coli serogroups O28, O117, O119, O126, and 146 were sequenced, and the genes were annotated. There were 7, 11, 9, 10, and 11 open reading frames in E. coli O28, O117, O119, O126, and O146, respectively, and unique sequences in these serogroups were identified. The E. coli typing arrays can be expanded to include unique sequences from these and additional serogroups. Thus, DNA microarrays spotted with either oligonucleotides or PCR products, followed by hybridization with labeled long PCR products are feasible approaches for identifying E. coli strains based on O types, which could replace serogrouping using antisera. |