Teagasc, Food Research Centre, Moorepark, Fermoy, Cork, Ireland.
J Appl Microbiol. 2011 Sep;111(3):616-24. doi: 10.1111/j.1365-2672.2011.05075.x. Epub 2011 Jul 4.
Using a flow cytometry (FC)-based approach in combination with four selected fluorescent probes, the biochemical pathway activated following the adaptation of Cronobacter spp. to lethal heat stress was investigated. This approach assessed the physiological changes induced in four strains of Cronobacter spp.
Using the commercially available live/dead viability assessment fluorescence probes, live, injured or dead bacterial cells were studied. Cellular respiration and membrane potential were evaluated using the dye-labelled probe 3,3'-dihexylocarbocyanine iodide, metabolic activity was evaluated using a fluorescein diacetate (FDA) probe, intracellular pH changes were measured using a carboxy-fluorescein diacetate succinimidyl ester probe, and reactive oxygen species were measured using a hydroethidine fluorescent probe. Adaptation to lethal heat stress induced physiological changes that potentially improve the survival of Cronobacter spp.
These data showed that in situ assessment of physiological behaviour of lethally stressed cells using multiparameter FC is a useful, rapid and sensitive tool to study and assess the viability and physiological state of Cronobacter cells.
This study shows that FC is a valuable tool in the study of physiological aspects of increased survival because of sublethal adaptation to heat.
本研究采用流式细胞术（FC）结合四种荧光探针，研究了 Cronobacter 属适应致死热应激后激活的生化途径。该方法评估了四种 Cronobacter 属菌株的生理变化。
本研究使用市售的死活细胞活力评估荧光探针，研究了活细胞、受损细胞和死细胞。使用染料标记的探针 3,3'-二己基羰花青碘评估细胞呼吸和膜电位，使用荧光素二乙酸酯（FDA）探针评估代谢活性，使用羧基荧光素二乙酸琥珀酰亚胺酯探针测量细胞内 pH 变化，使用羟乙基啶荧光探针测量活性氧。适应致死热应激诱导了潜在改善 Cronobacter 属生存能力的生理变化。
这些数据表明，使用多参数 FC 原位评估致死应激细胞的生理行为是一种有用、快速和敏感的工具，可用于研究和评估 Cronobacter 细胞的活力和生理状态。
本研究表明，FC 是研究因亚致死适应热而增加生存能力的生理方面的有价值的工具。
