Thauera spp., Another Prominent Denitrifying Bacteria in the Methanol-Fed Activated Sludge

摘要

Using quantitative polymerase chain reaction techniques, we quantified three denitrifying genera Paracoccus, Thauera and Pseudomonas. Thauera spp. (3.1 × 10~(12) ± 2.9 × 10~(12) cells/L) were relatively abundant than Paracoccus spp. (1.8 × 10~(10) ± 1.1 × 10~(10) cells/L) or Pseudomonas spp. (3.8 × 10~9 ± 3.4 × 10~9 cells/L) in the aeration tank of a methanol fed plant. Seasonal variation in denitrifying bacterial community produced a positive correlation between denitrification and the population concentrations of Thauera spp. or Paracoccus spp. in the methanol-fed activated sludge. Increased temperature ranging from 23.7 to 28.6C appeared to favor the growth of Thauera spp., while increased dissolved oxygen in the anoxic zone showed the unfavorable growth for Thauera spp. While Zoogloea was the second most abundant denitrifier identified and showed seasonal patterns different from Thauera spp.