National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, PR China.
National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, PR China.
Environ Int. 2023 Aug;178:108040. doi: 10.1016/j.envint.2023.108040. Epub 2023 Jun 15.
Antimony (Sb) is toxic to ecosystems and potentially to public health via its accumulation in the food chain. Bioavailability and toxicity of Sb have been reduced using various methods for the remediation of Sb-contaminated soil in most studies. However, Sb-contaminated soil remediation by microbial agents has been rarely evaluated. In this study, we evaluated the potential for the use of Comamonas testosteroni JL40 in the bioremediation of Sb-contamination. Strain JL40 immobilized more than 30 % of the Sb(III) in solution and oxidized over 18 % to Sb(V) for detoxification. Meanwhile, strain JL40 responds to Sb toxicity through such as Sb efflux, intracellular accumulation, biofilm production, and scavenging of reactive oxygen species (ROS), etc. The results of the pot experiment showed the average Sb content of the brown rice was decreased by 59.1%, 38.8%, and 48.4%, for 1.8, 50, and 100 mg/kg Sb spiked soils, respectively. In addition, the results of plant, soil enzyme activity, and rice agronomic trait observations showed that the application of strain JL40 could maintain the health of plants and soil and improve rice production. The single-step and sequential extraction of Sb from rhizosphere soil showed that strain JL40 also plays a role in Sb immobilization and oxidation in the soil environment. During rice potted cultivation, bacterial community analysis and plate counting showed that the strain JL40 could still maintain 10 CFU/g after 30 days of inoculation. With phenotypic and differential proteomics analysis, strain JL40 conferred Sb(III) tolerance by a combination of immobilization, oxidation, efflux and scavenging of ROS, etc. Our study demonstrates the application of Sb-immobilizing and oxidizing bacteria to lower soil Sb and reduce accumulation of Sb in rice. Our results provide guidance for bacterial remediation of Sb-contaminated soil.
锑（Sb）在生态系统中具有毒性，并且通过在食物链中的积累，对公共健康也具有潜在的毒性。在大多数研究中，已采用各种方法来修复 Sb 污染土壤，以降低 Sb 的生物利用度和毒性。然而，微生物剂修复 Sb 污染土壤的研究较少。在这项研究中，我们评估了 Comamonas testosteroni JL40 在 Sb 污染土壤生物修复中的应用潜力。固定化菌株 JL40 可固定溶液中超过 30%的 Sb(III)，并将超过 18%的 Sb(III)氧化为 Sb(V)以解毒。同时，菌株 JL40 通过 Sb 外排、细胞内积累、生物膜形成和清除活性氧物质（ROS）等方式来应对 Sb 毒性。盆栽实验结果表明，对于 1.8、50 和 100mg/kg Sb 污染土壤，糙米中 Sb 的平均含量分别降低了 59.1%、38.8%和 48.4%。此外，植物、土壤酶活性和水稻农艺性状的观察结果表明，菌株 JL40 的应用可以维持植物和土壤的健康并提高水稻产量。土壤根际 Sb 的单步和连续提取结果表明，菌株 JL40 也在土壤环境中发挥 Sb 固定和氧化作用。在水稻盆栽培养过程中，细菌群落分析和平板计数表明，接种 30 天后，菌株 JL40 仍可保持 10 CFU/g。通过表型和差异蛋白质组学分析，菌株 JL40 通过固定化、氧化、外排和清除 ROS 等多种方式赋予 Sb(III)耐受性。我们的研究表明，Sb 固定化和氧化细菌可用于降低土壤 Sb 含量并减少 Sb 在水稻中的积累。我们的研究结果为 Sb 污染土壤的细菌修复提供了指导。
