To investigate the characteristics and metabolic mechanism of short-cut denitrifying phosphorus-removing bacteria (SDPB) that are capable of enhanced biological phosphorus removal (EBPR) using nitrite as an electron a...To investigate the characteristics and metabolic mechanism of short-cut denitrifying phosphorus-removing bacteria (SDPB) that are capable of enhanced biological phosphorus removal (EBPR) using nitrite as an electron acceptor, an aerobic/anoxic sequencing batch reactor was operated under three phases. An SDPB-strain YC was screened after the sludge enrichment and was identified by morphological, physiological, biochemical properties and 16S rDNA gene sequence analysis. Denitrifying phosphorus-removing experiments were conducted to study anaerobic and anoxic metabolic mechanisms by analyzing the changes of chemical oxygen demand (COD), phosphate, nitrite, poly-β-hydroxybutyrate (PHB), and glycogen. The results show that strain YC is a non-fermentative SDPB similar to Paracoccus denitrificans. As a kind of non-fermentative bacteria, the energy of strain YC was mainly generated from phosphorus release (96.2%) under anaerobic conditions with 0.32 mg P per mg synthesized PHB. Under anoxic conditions, strain YC accumulated 0.45 mg P per mg degraded PHB, which produced most of energy for phosphate accumulation (91.3%) and a little for glycogen synthesis (8.7%). This metabolic mechanism of strain YC is different from that of traditional phosphorus-accumulating organisms (PAOs). It is also found that PHB, a kind of intracellular polymer, plays a very important role in denitrifying and accumulating phosphorus by supplying sufficient energy for phosphorous accumulation and carbon sources for denitrification. Therefore, monitoring ΔP/ΔPHB and ΔNO2--N/ΔPHB is more necessary than monitoring ΔP/ΔCOD,ΔNO2--N/ΔCOD, or ΔP/ΔNO2--N.展开更多
基金Supported by the Nafional Natural Science Foundation of China （51078008）, the Natural Science Foundation of Guangdong Province （06022869, 07003251）, and the National Key Scientific and Technological Project Water Pollution Control and Treatment （2008ZX07211-003, 2009ZX07314-009-003）.
文摘To investigate the characteristics and metabolic mechanism of short-cut denitrifying phosphorus-removing bacteria (SDPB) that are capable of enhanced biological phosphorus removal (EBPR) using nitrite as an electron acceptor, an aerobic/anoxic sequencing batch reactor was operated under three phases. An SDPB-strain YC was screened after the sludge enrichment and was identified by morphological, physiological, biochemical properties and 16S rDNA gene sequence analysis. Denitrifying phosphorus-removing experiments were conducted to study anaerobic and anoxic metabolic mechanisms by analyzing the changes of chemical oxygen demand (COD), phosphate, nitrite, poly-β-hydroxybutyrate (PHB), and glycogen. The results show that strain YC is a non-fermentative SDPB similar to Paracoccus denitrificans. As a kind of non-fermentative bacteria, the energy of strain YC was mainly generated from phosphorus release (96.2%) under anaerobic conditions with 0.32 mg P per mg synthesized PHB. Under anoxic conditions, strain YC accumulated 0.45 mg P per mg degraded PHB, which produced most of energy for phosphate accumulation (91.3%) and a little for glycogen synthesis (8.7%). This metabolic mechanism of strain YC is different from that of traditional phosphorus-accumulating organisms (PAOs). It is also found that PHB, a kind of intracellular polymer, plays a very important role in denitrifying and accumulating phosphorus by supplying sufficient energy for phosphorous accumulation and carbon sources for denitrification. Therefore, monitoring ΔP/ΔPHB and ΔNO2--N/ΔPHB is more necessary than monitoring ΔP/ΔCOD,ΔNO2--N/ΔCOD, or ΔP/ΔNO2--N.
