Institute of Soil and Water Resources and Environmental Science, College of Environment and Resource Sciences, Zhejiang University, Hangzhou, 310058, China; Zhejiang Provincial Key Laboratory of Agricultural Substrates and Environment, Zhejiang University, Hangzhou, 310058, China.
Institute of Soil and Water Resources and Environmental Science, College of Environment and Resource Sciences, Zhejiang University, Hangzhou, 310058, China; Zhejiang Provincial Key Laboratory of Agricultural Substrates and Environment, Zhejiang University, Hangzhou, 310058, China.
Environ Pollut. 2020 Jun;261:114225. doi: 10.1016/j.envpol.2020.114225. Epub 2020 Feb 21.
The presence of Eschericia coli O157:H7 in the natural environment is a serious threat to human health. The native microbial community in soil plays an important role in resisting E. coli O157:H7 invasion. This study examined the responses of soil microbial community to E. coli O157:H7 invasion during a 32-day incubation. The E. coli O157:H7 persisted longer in γ-irradiated soil than non-irradiated soil while glucose addition decreased its persistence in the irradiated soil which was associated with an increasing recovery of the native community. The invasion of E. coli O157:H7 increased soil organic carbon mineralization, an indicator of microbial activity, in both non-irradiated and irradiated soils, while glucose addition significantly promoted the carbon mineralization process. The 16S rRNA sequencing data showed the gradual recovery of the native bacterial population including specific taxa such as proteobacteria and actinobacteria following irradiation. It is concluded that soil microbial function and structure can affect persistence of E. coli O157:H7 and that lower biodiversity of the native community favors its persistence.
大肠杆菌 O157:H7 在自然环境中的存在对人类健康构成严重威胁。土壤中的本地微生物群落对于抵抗大肠杆菌 O157:H7 的入侵起着重要作用。本研究在 32 天的孵育过程中，检测了土壤微生物群落对大肠杆菌 O157:H7 入侵的反应。与未辐照土壤相比，γ 辐照土壤中大肠杆菌 O157:H7 的持续时间更长，而葡萄糖的添加减少了其在辐照土壤中的持续时间，这与本地群落的恢复有关。大肠杆菌 O157:H7 的入侵增加了非辐照和辐照土壤中土壤有机碳矿化作用，这是微生物活性的一个指标，而葡萄糖的添加则显著促进了碳矿化过程。16S rRNA 测序数据显示，在辐照后，本地细菌种群包括变形菌门和放线菌门等特定类群逐渐恢复。因此可以得出结论，土壤微生物功能和结构会影响大肠杆菌 O157:H7 的持续存在，而本地群落的生物多样性较低则有利于其持续存在。
