Green fluorescent protein labeling of food pathogens Yersinia enterocolitica and Yersinia pseudotuberculosis

•Y. enterocolitica (biovar 1A, 2, 4) and Y. pseudotuberculosis were successfully transformed with TurboGFP expression vector•Bright green fluorescence over long time periods was achieved for Y. enterocolitica biovar 1A, 2 and Y. pseudotuberculosis•No adverse effect on growth behavior of labeled strains compared to parental strains was identified

Labeling of bacteria with marker genes, such as green fluorescent protein, is a useful and practicable tool for tracking and enumerating bacterial cells in a complex environment e.g. discrimination from the indigenous background population. In this study, novel TurboGFP prokaryotic expression vector was utilized for labeling of Yersinia species. Y. enterocolitica biovar 1A, biovar 2, biovar 4 and Y. pseudotuberculosis were successfully transformed with the vector and expressed bright green fluorescence that was even detectable visually by eye. No adverse effects were observed in growth behavior of the labeled strains compared to wild type (parental) strains and vector maintenance for longer time periods could be achieved for Y. enterocolitica biovar 1A, Y. enterocolitica biovar 2 and Y. pseudotuberculosis.