Flow-through imaging cytometry for characterization of Salmonella subpopulations in alfalfa sprouts, a complex food system.

摘要: We recently developed an approach combining fluorescence in situ hybridization (FISH) and flow cytometry for detecting low levels of Salmonella spp. (approximately 10(3) cells/mL sprout wash) against high naturally occurring flora 10(7)-10(8) CFU/g sprouts). Although this "FISH flow" provided rapid presence/absence testing complex food system, it was not capable more nuanced tasks, such as probing the phenotypic complexity microbes present sprouts or determining physical interactions with these microbes, debris. In study, we have combined FISH-based labeling washes flow-through imaging (FT-IC), using ImageStream 100, a commercial FT-IC instrument. This enables image-based characterization various subpopulations interest within samples. Here, demonstrate ability to unambiguously identify cells, cell aggregates other events based on both morphology status after reaction Salmonella-targeted probe cocktail. Our directly explore nature expands layers information possible from cytometric analyses samples clearly demonstrates that "a picture is worth thousand dots".