College of Environmental Sciences, Sichuan Agricultural University, 611130 Chengdu, China; Microbial Ecology, Department of Biology, Lund University, Ecology Building, 22362 Lund, Sweden.
Microbial Ecology, Department of Biology, Lund University, Ecology Building, 22362 Lund, Sweden.
J Hazard Mater. 2021 Jun 5;411:124962. doi: 10.1016/j.jhazmat.2020.124962. Epub 2021 Jan 4.
Microbial resistance to antibiotics is a growing challenge to human health. Recent evidence has indicated that antibiotic resistance can be co-selected for by exposure to heavy metals in agricultural soils. It remains unknown if this is a concern in other environments contaminated by metals. We here investigated soil microbial activities, composition and tolerance to heavy metals and antibiotics in a mining soil survey. We found that microbial respiration, growth, and biomass were affected by available metal concentrations. Most of the variation in microbial PLFA composition was explained by differences in heavy metal and pH. Additionally, pollution-induced bacterial community tolerance to toxicants including Cu, Pb, Zn, tetracycline and vancomycin was determined. Although only bacterial tolerance to Pb increased with higher levels of metals, the links between bacterial metal tolerance and soil metal concentrations were clear when considered together with previously published reports, suggesting that bacterial metal tolerance were universally elevated in the surveyed soils. The induced levels of heavy metal tolerance coincided with elevated levels of tolerance to vancomycin, but not to tetracycline. Our study showed that heavy metals can co-select for resistance to clinically important antibiotics also in ecosystems without manure input or antibiotic pollution.
微生物对抗生素的耐药性是对人类健康的一个日益严峻的挑战。最近的证据表明，抗生素耐药性可能会因暴露于农业土壤中的重金属而共同选择。目前尚不清楚在其他受到金属污染的环境中是否存在这种担忧。我们在此通过一项矿区土壤调查，研究了土壤中微生物的活性、组成以及对重金属和抗生素的耐受能力。我们发现，微生物的呼吸作用、生长和生物量会受到可用金属浓度的影响。微生物 PLFA 组成的大部分变异可由重金属和 pH 值的差异来解释。此外，我们还确定了污染诱导的细菌群落对包括铜、铅、锌、四环素和万古霉素等有毒物质的耐受能力。尽管只有细菌对 Pb 的耐受能力随金属水平的升高而增加，但当与以前发表的报告一起考虑时，细菌对金属的耐受能力与土壤金属浓度之间的联系是明确的，这表明在调查的土壤中，细菌对金属的耐受能力普遍提高。重金属的诱导耐受水平与万古霉素的耐受水平升高相一致，但与四环素的耐受水平升高不一致。我们的研究表明，在没有粪肥投入或抗生素污染的生态系统中，重金属也可以共同选择对抗生素的耐药性，而这些抗生素对临床很重要。
