College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao 266580, PR China.
College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao 266580, PR China; State Key Laboratory of Petroleum Pollution Control, Qingdao 266580, PR China.
Sci Total Environ. 2022 Dec 20;853:158388. doi: 10.1016/j.scitotenv.2022.158388. Epub 2022 Aug 29.
Microorganisms that can simultaneously remediate organic pollutants and heavy metal contamination are great significance in bioremediation. Nevertheless, reports of such microorganisms are still scarce. Here, Pseudomonas sp. YH-1 and Rhodococcus sp. YH-3 were isolated and identified, and they showed greater tolerance to hexavalent (VI) (750 and 800 mg·L). The constructed bacteria consortium YH (YH-1:YH-3 = 1:1) could simultaneously degrade 41.69% of pyrene (50 mg·L) and remove 76.67% of Cr(VI) (30 mg·L) within 5 days. The potential mechanism of Cr(VI) tolerance of YH was further explored by genomic and microscopic analysis. The results showed that YH responded to Cr(VI) stress mainly through efflux of Cr(VI) by chrA and copZ, chromate reduction, DNA-repaired proteases reduces ROS damage, and biosorption by carboxyl, hydroxyl, amino functional groups. Strains YH-1 and YH-3 also contained a variety of genes associated with resistance to other heavy metals, such as cadmium (czcBD), mercury (merAPTR), manganese (mntABC) and copper (copAC, cusABRF and pcoBD). Based on GC-MS and genomic analysis, pyrene was degraded via salicylic acid and phthalic acid pathways. Moreover, a great number of genes related to aromatic hydrocarbon catabolism were identified in the genomes of YH-1 and YH-3. These results confirmed the potential application of the bacteria consortium YH in the bioremediation of water and soil co-contaminated with PAHs-heavy metals.
能够同时修复有机污染物和重金属污染的微生物在生物修复中具有重要意义。然而，此类微生物的报道仍然很少。在这里，分离并鉴定了假单胞菌 YH-1 和红球菌 YH-3，它们对六价（VI）（750 和 800mg·L）具有更大的耐受性。构建的细菌联合体 YH（YH-1：YH-3=1：1）可以在 5 天内同时降解 50mg·L 的芘的 41.69%和 30mg·L 的 Cr(VI)的 76.67%。通过基因组和显微镜分析进一步探讨了 YH 对 Cr(VI)耐受性的潜在机制。结果表明，YH 主要通过 chrA 和 copZ 排出 Cr(VI)、铬酸盐还原、DNA 修复蛋白酶减少 ROS 损伤以及羧基、羟基、氨基等官能团的生物吸附来响应 Cr(VI)胁迫。菌株 YH-1 和 YH-3 还含有多种与其他重金属抗性相关的基因，如镉（czcBD）、汞（merAPTR）、锰（mntABC）和铜（copAC、cusABRF 和 pcoBD）。基于 GC-MS 和基因组分析，发现芘通过水杨酸和邻苯二甲酸途径降解。此外，在 YH-1 和 YH-3 的基因组中还鉴定出大量与芳烃代谢相关的基因。这些结果证实了细菌联合体 YH 在同时含有多环芳烃-重金属的水和土壤生物修复中的潜在应用。
