摘要

       肥料中的抗生素抗性基因（ARG）和抗生素抗性细菌（ARB）对人类健康构成威胁，据报道，施肥后它们在土壤中的变异。但是，一些重要的问题，例如在施肥后在土壤中观察到的ARG和ARB的起源，无论肥料类型如何（例如，核心（共享）ARGs和ARB），它们都存在于土壤中，以及各种ARG亚型对土壤的贡献。土壤抗生素抗药性，需要解决。在这项研究中，使用宏基因组测序研究了长期（9年）施用有机（肥料）和无机（化学）肥料对种植蔬菜的温室土壤中ARG的影响。结果表明，有机和无机肥料的施用均增加了土壤ARGs的多样性和丰度。有机肥（OF）中的主要ARG类型不同于有机肥处理过的土壤（SO），无机肥处理过的土壤（SI）和无肥料控制区（SC）。核心ARG丰度的差异反映了SC，SI和SO之间ARG分布的变化。 OF可能是土壤中ARG亚型升高的来源，几乎所有土壤核心ARG亚型都可以在有机肥料中检出。 OF使土壤中富集了15种ARG类型，某些ARG亚型如sul1，sul2，tetX和tetL可能来自OF，而其他诸如vanR，tcmA，rosB和mexF的亚型可能来自土壤中的原生微生物。发现营养因素会影响施肥土壤中的ARG分布。总之，这项研究揭示了施肥后土壤总ARG数量及其相对丰度增加的可能原因，这将有助于控制ARGs和ARB的传播。

        Antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB) in fertilizers pose risks to human health and their variation in soil after fertilization has been reported. However, some important questions, such as the origin of ARG and ARB observed in soil following fertilization, which are present in soil regardless of fertilizer type (i.e., core (shared) ARGs and ARB), and the contribution of various ARG subtypes to the soil antibiotic resistome, need to be addressed. In this study, the effects of a long-term (9-year) application of organic (manure) and inorganic (chemistry) fertilizers on ARGs in greenhouse soils growing vegetables were investigated using metagenomic sequencing. The results showed that both organic and inorganic fertilizers application increased the diversity and abundance of soil ARGs. The dominant ARG types in organic fertilizer (OF) were different from that in organic fertilizer treated soil (SO), inorganic fertilizer treated soil (SI) and no fertilizer control plots (SC). The difference of core ARGs abundance reflected the variation of ARG profiles among SC, SI and SO. The OF is likely a source of the elevated ARG subtypes in soil and almost all the soil core ARG subtypes can be detected in organic fertilizer. Fifteen ARG types were enriched in the soil with OF, and some ARG subtypes such as sul1, sul2, tetX and tetL might derived from OF while others including as vanR, tcmA, rosB, and mexF might be from indigenous microbes in soil. The nutrition factors were found to influence the ARG profiles in fertilized soil. In summary, this study revealed the possible reason for the soil total ARG numbers and their relative abundance increase after fertilization, which will facilitate the control of ARGs and ARB dissemination.

        https://www.sciencedirect.com/science/article/abs/pii/S0147651319304622?via%3Dihub