Genetic potential for pentachlorophenol degradation at historically contaminated groundwater sites

Sampling

Novel primers for pcpB allowed us for the first time to investigate the genetic potential for degradation of the priority pollutant pentachlorophenol (PCP) in situ. We assessed whether pcpB is detectable at chlorophenol-polluted groundwater sediments at two sites, and if its abundance reflects differences in PCP concentration. We also sought correlations between the abundance and diversity of pcpB and sphingomonads that might indicate host specificity. pcpB was highly abundant, with copy numbers of up to 7% of bacterial 16S rRNA gene copies, and its relative abundance was linked to spatial or temporal differences in groundwater PCP concentration at two historically polluted sites, indicating ecological relevance of the pathway in situ. pcpB abundance was associated with sphingomonad abundance, but independent of sphingomonad community composition. This provides the first culture-independent support for widespread horizontal transfer of PCP degradation potential among sphingomonads in chlorophenol-polluted groundwaters.

Method steps

1. Pipeline used: https://www.ebi.ac.uk/metagenomics/pipelines/4.1