PRJNA229802
Diversity of bacteria, archaea, fungi and algae in coal mine drainage remediation systems treating elevated manganese
Water discharging from abandoned coal mines can contain extremely high manganese levels, and removing this metal is an ongoing challenge. Passive Mn remediation systems promote the growth of certain bacteria and fungi that catalyze the transformation of soluble Mn(II) to insoluble Mn(III/IV) minerals, but system performance is unpredictable. Mn-oxidizing organisms likely belong to complex communities that include algae and archaea, as well as bacteria and fungi that do not oxidize Mn. Community interactions could be modulating the efficiency of Mn oxidation in the treatment beds. Using a targeted sequencing approach, we aimed to determine the diversity and composition of microbial communities inhabiting several different Mn remediation systems, compared with surrounding uncontaminated soil, and to establish the abundance of known Mn-oxidizing microorganisms relative to the entire community. Four Mn treatment beds in Pennsylvania were selected, each treating metal-contaminated discharge from abandoned coal mines. Rock or sediment samples were collected near the influent, in the middle and near the effluent of each bed, as well as from surrounding uncontaminated soil. Amplicon pyrosequencing was carried out with primers targeting bacteria (small subunit rRNA), archaea (small subunit rRNA), fungi (internal transcribed spacer) and algae (plastid large subunit rRNA).