Exploring functional microbiota for uranium sequestration in Zoige uranium mine soil

ABSTRACT The Zoige uranium mine is situated in the harsh, cold northern region of Sichuan, characterized by its high altitude and fragile ecosystem. Uncovering the organisms that thrive in such extreme climates, particularly microorganisms, is of paramount importance for advancing bioremediation efforts. Herein, the potential functional microbiota for uranium sequestration in Zoige uranium mine soil was explored using high-throughput sequencing combined with bioinformatics analysis. Analysis of the physicochemical properties of soils showed that the concentration of uranium ranged from 35.20 to 40.62 µg·g −1 around the uranium mine. Bacterial communities differed significantly in soils around the Zoige uranium mine, with the most abundant phyla being Actinobacteria, Proteobacteria, Acidobacteria, Chloroflexi, Gemmatimonadota, Verrucomicrobia, and Firmicutes. Notably, Actinobacteria was considered a biomarker for distinguishing soils with high uranium by linear discriminant analysis effect size. Meanwhile, the correlation analysis demonstrated that Firmicutes and Cyanobacteria were significantly and positively associated with uranium in soil samples, with the correlation coefficients being 0.8601 and 0.7832, respectively. Furthermore, the phylogenetic investigation of communities by reconstruction of unobserved states analysis revealed that the bacterial microbiota was mainly enriched in biosynthesis function in these soils. Interestingly, the abundance of functional genes involved in amino acid biosynthesis increased whereas that related to fatty acid biosynthesis decreased with an increase in uranium content. Taken together, Actinobacteria, Firmicutes, and Cyanobacteria were the potential functional microbiota for uranium sequestration via amino acid and fatty acid biosynthesis pathways in Zoige uranium mine soil. These findings are conducive to obtaining functional strains for developing microbial remediation technologies for uranium contamination. IMPORTANCE Based on the significance of the Zoige uranium mine and its unique ecological environment, this study emphasizes the necessity of in situ bioremediation. Herein, the potential functional microbiota for uranium sequestration in Zoige uranium mine soil was explored using high-throughput sequencing and bioinformatics analysis. Actinobacteria, Firmicutes, and Cyanobacteria were the potential functional microbiota in Zoige uranium mine soils. These microbes interacted and tolerated uranium via amino acid and fatty acid biosynthesis pathways. These findings provide insights into the functional microbiota of uranium sequestration, which are conducive to developing microbial resources and bioremediation technology for treating uranium contamination.