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Molecular and genetic characterization of cytochrome oxidase negative Aeromonas salmonicida isolated from coho salmon (Oncorhynchus kisutch)

J.D. Teska·R. C. Cipriano·W. B. Schill
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Abstract

Cytochrome oxidase variants of the bacterial fish pathogen, Aeromonas salmonicida , were characterized for genetic and molecular homology with cytochrome oxidase-positive isolates that typically induce furunculosis in salmonids. Protein and lipopolysaccharide moieties of the cytochrome oxidase-negative variants were similar to their typical counterparts, based on sodium-dodecyl-sulfate polyacrylamide gel electrophoresis. Pathogenicity of aberrant isolates to brook trout ( Salvelinus fontinalis ) was similar to typical cytochrome oxidase-positive isolates. Colorimetric deoxyribonucleic acid (DNA) hybridization in 96-well microplates yielded homology values greater than 82.5% for typical aberrant A. salmonicida isolates when photobiotinylated DNA for reference A. salmonicida 3.101 was used as a probe. The only variation of these isolates from typical A. salmonicida was a negative cytochrome oxidase reaction.

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J.D. Teska, R. C. Cipriano, W. B. Schill. 1992. Molecular and genetic characterization of cytochrome oxidase negative Aeromonas salmonicida isolated from coho salmon (Oncorhynchus kisutch). https://doi.org/10.7589/0090-3558-28.4.515

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