Bacterial communities analyzed by 16S rRNA Illumina and bamA clone library sequencing in (i) coal tar polluted groundwater (Thuringia gasworks site, Germany) and in (ii) toluene, ethylbenzene and p-xylene degrading nitrate-reducing enrichment cultures. Further, a putative 4-methylbenzoyl-CoA reductase gene cluster possibly involved in p-xylene degradation was identified.. Microbial communities at the Thuringia gasworks site

Aromatic compounds such as BTEX are among the main contaminants in coal tar polluted aquifers. The aim of this study was to profile the microbial communities at the Thuringia gasworks site along a pollutant gradient. We analyzed environmental samples and BTEX-degrading enrichment cultures obtained from the same site that utilize either toluene, ethylbenzene or p-xylene with nitrate. Community analyses were conducted by deep 16S rRNA Illumina sequencing and bamA clone library sequencing, a marker for anaerobic aromatic compound degradation. We further identified a putative 4-methylbenzoyl-CoA reductase gene cluster (mbrBCAD) by genome walking, which is possibly involved in the anaerobic degradation of p-xylene with nitrate.