Microbial consortia in mine water bioremediation: principles, design and practical applications

The impact of mining activities on water sources is a global concern, especially in water-scarce countries such as Southern Africa, Mediterranean region, western Asia, and South America. Bioremediation emerges as a feasible and attractive alternative to address this environmental issue. However, while biological sulfate reduction and the emerging use of using microbially induced carbonate precipitation (MICP) for remediating polluted mine water have gained attention, strategies for designing effective microbial consortia have seen little advancement. The performance of microbial consortia in these treatments can be quite variable. Most improvement strategies have focused mainly on bioreactor design and selecting suitable carbon sources, addressing technical aspects while neglecting the central players in this process: the microbes themselves. Enhancing consortium effectiveness requires revisiting foundational concepts such as monoculture, co-culture, division of labor, and bottom-up versus top-down approaches. While these concepts offer significant theoretical potential to improve consortium performance, they have seldom been applied in practice for mine water bioremediation. In this literature review, we revisit these principles and explore the integration of novel tools such as metagenomics and bioinformatics. These approaches can deepen our understanding of indigenous microbial diversity, uncover dynamic interactions among microbial species, and identify keystone species as potential candidates for bioremediation. By leveraging their genomic potential, it becomes possible to design consortia that are more efficient and better suited to support the recovery of contaminated water sources.