Temperature Significantly Affects the Plaquing and Adsorption Efficiencies of Listeria Phages.
Temperature Significantly Affects the Plaquing and Adsorption Efficiencies of Listeria Phages.
复制标题
DOI：
10.3389/fmicb.2016.00631
复制
发表时间：
2016
影响因子：
5.2
通讯作者：
Denes T
中科院分区：
文献类型：
--
作者：
Tokman JI;Kent DJ;Wiedmann M;Denes T
目前，感染李斯特菌的噬菌体被用于控制和检测重要的食源性病原体单核细胞增生李斯特菌；然而，环境条件对单增李斯特菌与其噬菌体之间相互作用的影响尚未得到深入探讨。在这里，我们检查了四种李斯特菌噬菌体（李斯特菌的 P70 样噬菌体和 P100 样噬菌体各两种）对在一定温度范围 (7–37°C) 下生长的单核细胞增生李斯特氏菌五株（代表血清型 1/2a、1/2b、4a 和 4b）的感染潜力。我们发现所有四种噬菌体的噬菌斑效率均受到温度的显着影响。有趣的是，在 37°C 下，四种噬菌体均未观察到噬菌斑。对 P100 类噬菌体 LP-048 和 LP-125 进行的吸附测定表明，与 30°C 相比，LP-048 在 37°C 时对敏感菌株的吸附效率严重降低，这表明 37°C 时宿主上可接近的鼠李糖（LP-048 的假定噬菌体受体）比 30°C 时要少得多。 LP-125 在 37°C 下吸附到宿主细胞上，表明 LP-125 在 37°C 下不能形成噬菌斑并不是由于吸附抑制。在 30°C 和 37°C 下，LP-048 对壁磷壁酸 (WTA) 中缺乏 N-乙酰氨基葡萄糖的突变菌株表现出比亲本菌株显着更高的吸附效率，表明 N-乙酰氨基葡萄糖与鼠李糖竞争 WTA 上的糖基化位点。这里提供的数据清楚地表明，单核细胞增多性李斯特菌可以获得免受噬菌体感染的生理庇护，在基于噬菌体的控制和检测应用的设计和实施时应仔细考虑这一点。
Listeria-infecting phages are currently being used to control and detect the important foodborne pathogen Listeria monocytogenes; however, the influence of environmental conditions on the interactions between L. monocytogenes and its phages has not been explored in depth. Here, we examined the infective potential of four Listeria phages (two each from the P70-like and P100-like phages of Listeria) against five strains of L. monocytogenes (representing serotypes 1/2a, 1/2b, 4a, and 4b) grown under a range of temperatures (7–37°C). We show that the plaquing efficiencies for all four phages were significantly affected by temperature. Interestingly, no plaques were observed for any of the four phages at 37°C. Adsorption assays performed with the P100-like phages, LP-048 and LP-125, showed that LP-048 had a severely reduced adsorption efficiency against susceptible strains at 37°C as compared to 30°C, suggesting that there is considerably less accessible rhamnose (LP-048’s putative phage receptor) on the host at 37°C than at 30°C. LP-125 adsorbed to host cells at 37°C, indicating that the inability for LP-125 to plaque at 37°C is not due to adsorption inhibition. LP-048 showed significantly higher adsorption efficiency against a mutant strain lacking N-acetylglucosamine in its wall teichoic acids (WTA) than the parental strain at both 30 and 37°C, suggesting that N-acetylglucosamine competes with rhamnose for glycosylation sites on the WTA. The data presented here clearly shows that L. monocytogenes can gain physiological refuge from phage infection, which should be carefully considered for both the design and implementation of phage-based control and detection applications.