Metagenomic analysis of relationships between the denitrification process and carbon metabolism in a bioaugmented full-scale tannery wastewater treatment plant

AbstractThe goal of this study was to investigate the relationship between the denitrification process and carbon metabolism in a full-scale tannery wastewater treatment plant bioaugmented with the microbial consortium BM-S-1. The metagenomic analysis of the microbial community showed thatBrachymonas denitrificans, a known denitrifier, was present at a high level in the treatment stages of buffering (B), primary aeration (PA), and sludge digestion (SD). The occurrences of the amino acid-degrading enzymes alpha ketoglutarate dehydrogenase ( α-KGDH) and tryptophan synthase were highly correlated with the presence of denitrification genes, such asnapA,narG,nosZ andnorB. The occurrence of glutamate dehydrogenase (GDH) was also highly paralleled with the occurrence of denitrification genes such asnapA,narG, andnorZ. The denitrification genes (nosZ,narG,napA,norB andnrfA) and amino acid degradation enzymes (tryptophan synthase, α-KGDH and pyridoxal phosphate dependent enzymes) were observed at high levels in B. This indicates that degradation of amino acids and denitrification of nitrate may potentially occur in B. The high concentrations of the fatty acid degradation enzyme groups (enoyl-CoA hydratase, 3-hydroxyacyl-CoA dehydrogenase and β-ketothiolase) were observed together with the denitrification genes, such asnapA,narG andnosZ. Phospholipase/carboxylesterase, enoyl-CoA hydratase/isomerase, acyl-CoA dehydrogenase, phenylacetate degradation enzyme and 3-hydroxyacyl-CoA dehyd...
Source: World Journal of Microbiology and Biotechnology - Category: Microbiology Source Type: research