Bearson Bradley L, Douglass Cameron H, Duke Stephen O, Moorman Thomas B, Tranel Patrick J
USDA-ARS, National Laboratory for Agriculture and the Environment, Ames, Iowa, USA.
USDA, Office of the Chief Economist, Office of Pest Management Policy, Washington, District of Columbia, USA.
J Environ Qual. 2025 Jan-Feb;54(1):160-180. doi: 10.1002/jeq2.20655. Epub 2024 Nov 25.
The evolution and spread of antibiotic resistance are problems with important consequences for bacterial disease treatment. Antibiotic use in animal production and the subsequent export of antibiotic resistance elements in animal manure to soil is a concern. Recent reports suggest that exposure of pathogenic bacteria to glyphosate increases antibiotic resistance. We review these reports and identify soil processes likely to affect the persistence of glyphosate, antibiotic resistance elements, and their interactions. The herbicide molecular target of glyphosate is not shared by antibiotics, indicating that target-site cross-resistance cannot account for increased antibiotic resistance. The mechanisms of bacterial resistance to glyphosate and antibiotics differ, and bacterial tolerance or resistance to glyphosate does not coincide with increased resistance to antibiotics. Glyphosate in the presence of antibiotics can increase the activity of efflux pumps, which confer tolerance to glyphosate, allowing for an increased frequency of mutation for antibiotic resistance. Such effects are not unique to glyphosate, as other herbicides and chemical pollutants can have the same effect, although glyphosate is used in much larger quantities on agricultural soils than most other chemicals. Most evidence indicates that glyphosate is not mutagenic in bacteria. Some studies suggest that glyphosate enhances genetic exchange of antibiotic-resistance elements through effects on membrane permeability. Glyphosate and antibiotics are often present together in manure-treated soil for at least part of the crop-growing season, and initial studies indicate that glyphosate may increase abundance of antibiotic resistance genes in soil, but longer term investigations under realistic field conditions are needed. Although there are demonstratable interactions among glyphosate, bacteria, and antibiotic resistance, there is limited evidence that normal use of glyphosate poses a substantial risk for increased occurrence of antibiotic-resistant, bacterial pathogens. Longer term field studies using environmentally relevant concentrations of glyphosate and antibiotics are needed.
抗生素耐药性的演变与传播是对细菌性疾病治疗产生重要影响的问题。动物生产中抗生素的使用以及随后动物粪便中的抗生素耐药性元件向土壤的输出令人担忧。最近的报告表明，病原菌接触草甘膦会增加抗生素耐药性。我们回顾这些报告，并确定可能影响草甘膦、抗生素耐药性元件及其相互作用持久性的土壤过程。草甘膦的除草剂分子靶点与抗生素不同，这表明靶点交叉耐药不能解释抗生素耐药性的增加。细菌对草甘膦和抗生素的耐药机制不同，并且细菌对草甘膦的耐受性或耐药性与对抗生素耐药性的增加并不一致。在抗生素存在的情况下，草甘膦可以增加外排泵的活性，外排泵赋予对草甘膦的耐受性，从而使抗生素耐药性的突变频率增加。这种效应并非草甘膦所特有，因为其他除草剂和化学污染物也可能有相同的效应，尽管草甘膦在农业土壤中的使用量比大多数其他化学品要大得多。大多数证据表明草甘膦对细菌没有致突变性。一些研究表明，草甘膦通过影响膜通透性增强抗生素耐药性元件的基因交换。在粪肥处理的土壤中，草甘膦和抗生素在作物生长季节的至少部分时间里经常同时存在，初步研究表明草甘膦可能会增加土壤中抗生素耐药基因的丰度，但需要在实际田间条件下进行更长期的调查。虽然草甘膦、细菌和抗生素耐药性之间存在可证明的相互作用，但仅有有限的证据表明正常使用草甘膦会对耐药细菌病原体的增加构成重大风险。需要使用与环境相关浓度的草甘膦和抗生素进行更长期的田间研究。
