The quantification, efficiency, and possible mechanisms of mercury phytoremediation by endophytic bacteria are poorly understood. Here we selected 8 out of 34 previously isolated endophytic bacterial strains with a broad resistance profile to metals and 11 antibiotics: Acinetobacter baumannii BacI43, Bacillus sp. BacI34, Enterobacter sp. BacI14, Klebsiella pneumoniae BacI20, Pantoea sp. BacI23, Pseudomonas sp. BacI7, Pseudomonas sp. BacI38, and Serratia marcescens BacI56. Except for Klebsiella pneumoniae BacI20, the other seven bacterial strains promoted maize growth on a mercury-contaminated substrate. Acinetobacter baumannii BacI43 and Bacillus sp. BacI34 increased total dry biomass by approximately 47%. The bacteria assisted mercury remediation by decreasing the metal amount in the substrate, possibly by promoting its volatilization. The plants inoculated with Serratia marcescens BacI56 and Pseudomonas sp. BacI38 increased mercury volatilization to 47.16% and 62.42%, respectively. Except for Bacillus sp. BacI34 and Pantoea sp. BacI23, the other six bacterial strains favored mercury bioaccumulation in plant tissues. Endophytic bacteria-assisted phytoremediation contributed to reduce the substrate toxicity assessed in different model organisms. The endophytic bacterial strains selected herein are potential candidates for assisted phytoremediation that shall help reduce environmental toxicity of mercury-contaminated soils.

对内生细菌对汞进行植物修复的量化，效率和可能的机理了解甚少。在这里，我们从34个先前分离的内生细菌菌株中选择了8个，它们对金属和11种抗生素具有广泛的耐药性：鲍曼不动杆菌BacI43，芽孢杆菌。BacI34，肠杆菌属。BacI14，肺炎克雷伯菌BacI20，泛菌。BacI23，假单胞菌属。BacI7，假单胞菌属。BacI38和粘质沙雷氏菌BacI56。除肺炎克雷伯氏菌BacI20外，其他七种细菌菌株均在受汞污染的基质上促进了玉米的生长。鲍曼不动杆菌BacI43和芽孢杆菌sp。BacI34使总干生物量增加了约47％。细菌通过减少基质中的金属含量（可能通过促进其挥发）来辅助汞的修复。接种粘质沙雷氏菌BacI56和假单胞菌sp。的植物。BacI38使汞挥发分别增加到47.16％和62.42％。除芽孢杆菌属。BacI34和Pantoeasp。BacI23，其他六种细菌菌株都支持植物组织中汞的生物积累。内生细菌辅助的植物修复有助于减少在不同模型生物中评估的底物毒性。本文选择的内生细菌菌株是辅助植物修复的潜在候选者，该植物应有助于减少汞污染土壤的环境毒性。