Rapid confirmation of Listeria monocytogenes isolated from foods by a colony blot assay using a digoxigenin-labeled synthetic oligonucleotide probe.

摘要: Abstract An oligodeoxyribonucleotide probe based on the sequence of a 321-bp internal fragment msp gene encoding major secreted polypeptide Listeria monocytogenes was labeled with digoxigenin by using terminal deoxynucleotidyl transferase. The specificity digoxigenin-labeled determined dot blot assays. reacted all strains L. tested (12 12 representing five serotypes). did not react any other species or gram-positive bacteria (Brochothrix, Erysipelothrix, Corynebacterium, Rhodococcus, Lactobacillus, Leuconostoc, Bacillus, Staphylococcus, and Streptococcus). used to develop colony assay for rapid confirmation Listeria-selective agars which had been streaked food enrichment cultures. Forty-eight samples were conventional culture DNA assay. sensitivity 100 97%, respectively.