Acid Mine Drainage (AMD) Induced Gut Microbiota Alteration in Prosilocerus akamusi: Potential Role of Core Bacteria in AMD Resistance

Acid mine drainage (AMD) presents a significant global environmental challenge due to high levels of hydrogen ions (H⁺), sulfate (SO₄^2-), and metal ions. While previous studies have shown that Prosilocerus akamusi larvae can withstand such harsh conditions, their specific resistance to AMD remains unclear. This research demonstrates that P. akamusi larvae can improve water quality by increasing pH levels and reducing sulfate and metal concentrations (Mn, Fe, Ni, Cu, Zn, Cd, and Pb) in AMD samples. Exposure to AMD significantly altered the composition, structure, and diversity of gut microbial communities in these larvae, notably increasing the relative abundance of Serratia fonticola and unclassified Yersinia. Variance partitioning analysis revealed that factors like metal ions (Fe, Mn, Ni), SO₄^2- concentration, and pH accounted for 99.71% of the variation within microbial communities. Both S. fonticola and unclassified Yersinia exhibited positive correlations with pH but negative correlations with SO₄^2- and metal ions. A higher abundance of genes related to acid tolerance, metal tolerance, and sulfur metabolism was observed in both bacterial groups. These findings suggest that the natural gut bacteria in this insect play a vital role in mitigating AMD-induced stresses by enhancing detoxification processes, specifically in the H⁺/sulfate metabolism pathway, as well as in metal ion transport, efflux, and resistance protein functions, thereby bolstering host defense mechanisms. The current study enhances our understanding of the tolerance mechanisms of P. akamusi larvae to AMD stress and offers important references for potential applications in AMD remediation.