School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China; Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha 410083, China.
Department of Botany and Microbiology, College of Science, King Saud University, P. O. Box 2455, Riyadh 11451, Saudi Arabia.
Sci Total Environ. 2024 Dec 1;954:176385. doi: 10.1016/j.scitotenv.2024.176385. Epub 2024 Sep 18.
Microbial communities as the most important and active component of soil play a crucial role in the geochemical cycling of toxic metal(loid)s in the Pb and Zn smelting site soils. However, the relationships between soil microbial communities and the fractions of toxic metal(loid)s and the succession of soil microbial community and functions after enrichment cultivation have rarely been analyzed. In this study, the diversity and composition of microbial communities in soils before and after enrichment cultivation were investigated by high-throughput sequencing. And the co-occurrence relationships between soil microbial community after enrichment cultivation and MRGs genes were also analyzed through the BacMet database. Results showed that the dominant genus in the soils was Lactobacillus and Stenotrophomonas. The soil microbial community exhibited a notable correlation with Cd, Pb, and As, among which Cd exerted the most profound impact. Alishewanella, Pseudomonas, Massilia and Roseibacillus were significantly correlated with the fraction of Cd. After enrichment cultivation, the number of genera decrease to 96. And the dominant genus changed to Acinetobacter, Bacillus, Comamonas, Lysobacter, and Pseudoxanthomonas. High abundance of metal resistance genes (MRGs) including zntA, fpvA, zipB, cadA, czcA, czcB, czcC, zntA, arsR, pstS and pstB was found in the microbial community after enrichment cultivation. The potential host genus for MRGs was Acinetobacter, Comamonas, Lysinibacillus, Azotobacter, Bacillus, Lysobacter, Cupriavidus, Pseudoxanthomonas, and Thermomonas. Additionally, these microbial community after enrichment cultivation possessing pathways of bacterial chemotaxis and two-component systems was enabled them to adapt to the polluted environment. These observations provided potential guidance for microbe isolation and the development of strategies for the bioremediation of toxic metal(loid)s polluted soils.
微生物群落作为土壤中最重要和最活跃的组成部分，在 Pb 和 Zn 冶炼场地土壤中有毒金属（类）的地球化学循环中起着至关重要的作用。然而，土壤微生物群落与有毒金属（类）的形态以及富集培养后土壤微生物群落的演替和功能之间的关系很少被分析。在本研究中，通过高通量测序研究了富集培养前后土壤微生物群落的多样性和组成。并通过 BacMet 数据库分析了富集培养后土壤微生物群落与 MRGs 基因之间的共同发生关系。结果表明，土壤中优势属为 Lactobacillus 和 Stenotrophomonas。土壤微生物群落与 Cd、Pb 和 As 呈显著相关，其中 Cd 影响最大。Alishewanella、Pseudomonas、Massilia 和 Roseibacillus 与 Cd 形态显著相关。富集培养后，属的数量减少到 96 个。优势属变为 Acinetobacter、Bacillus、Comamonas、Lysobacter、和 Pseudoxanthomonas。在富集培养后的微生物群落中发现了大量的金属抗性基因（MRGs），包括 zntA、fpvA、zipB、cadA、czcA、czcB、czcC、zntA、arsR、pstS 和 pstB。MRGs 的潜在宿主属为 Acinetobacter、Comamonas、Lysinibacillus、Azotobacter、Bacillus、Lysobacter、Cupriavidus、Pseudoxanthomonas 和 Thermomonas。此外，这些富集培养后的微生物群落具有细菌趋化性和双组分系统的途径，使它们能够适应污染环境。这些观察结果为微生物分离和开发受有毒金属（类）污染土壤的生物修复策略提供了潜在指导。
