旨在分析陶厄氏菌属(Genus Thuaera)中的一株菌株Thauera sp.K11对含酚废水中酚类化合物的降解作用和途径。以石化污水厂分离菌株K11为研究对象,克隆其16S r RNA基因和关键酶基因,并进行系统发育分析,在基因水平探究苯酚降解机理;利用...旨在分析陶厄氏菌属(Genus Thuaera)中的一株菌株Thauera sp.K11对含酚废水中酚类化合物的降解作用和途径。以石化污水厂分离菌株K11为研究对象,克隆其16S r RNA基因和关键酶基因,并进行系统发育分析,在基因水平探究苯酚降解机理;利用气相色谱技术检测酚类化合物降解效果和苯酚降解机理。结果显示,利用16S r RNA系统学分析发现K11是陶厄氏菌属的一株细菌。该菌对11种酚类化合物具有降解作用,其中5种酚类化合物72 h的降解率>90%。克隆并获得了K11的苯酚羟化酶和邻苯二酚双加氧酶基因。酶活性测定表明,K11通过苯酚羟化酶催化苯酚转化为邻苯二酚,然后利用邻苯二酚-2,3-双加氧酶催化产生2-HMSA。陶厄氏菌Thauera sp.K11是一株能够降解多种酚类化合物的菌株,具有较强的酚类污染物降解能力,其通过苯酚→邻苯二酚→2-HMSA途径进行苯酚降解。展开更多
To investigate the effect of air-exposed biocathode（AEB） on the performance of singlechamber microbial fuel cell（SCMFC）, wastewater quality, bioelectrochemical characteristics and the electrode biofilms were resea...To investigate the effect of air-exposed biocathode（AEB） on the performance of singlechamber microbial fuel cell（SCMFC）, wastewater quality, bioelectrochemical characteristics and the electrode biofilms were researched. It was demonstrated that exposing the biocathode to air was beneficial to nitrogen removal and current generation. In Test 1 of 95%AEB, removal rates of ammonia, total nitrogen（TN） and chemical oxygen demand（COD）reached 99.34% ± 0.11%, 99.34% ± 0.10% and 90.79% ± 0.12%, respectively. The nitrogen removal loading rates were 36.38 g N/m3/day. Meanwhile, current density and power density obtained at 0.7 A/m3 and 104 m W/m3 respectively. Further experiments on opencircuit（Test 2） and carbon source（Test 3） indicated that this high performance could be attributed to simultaneous biological nitrification/denitrification and aerobic denitrification, as well as bioelectrochemical denitrification. Results of community analysis demonstrated that both microbial community structures on the surface of the cathode and in the liquid of the chamber were different. The percentage of Thauera, identified as denitrifying bacteria, maintained at a high level of over 50% in water, but decreased gradually in the AEB. Moreover, the genus Nitrosomonas, Alishewanella, Arcobacter and Rheinheimera were significantly enriched in the AEB, which might contribute to both enhancement of nitrogen removal and electricity generation.展开更多
We examined how long-term operation of anaerobic–oxic and anaerobic–anoxic sequencing batch reactors(SBRs) affects the enhanced biological phosphorus removal(EBPR)performance and sludge characteristics. The microbia...We examined how long-term operation of anaerobic–oxic and anaerobic–anoxic sequencing batch reactors(SBRs) affects the enhanced biological phosphorus removal(EBPR)performance and sludge characteristics. The microbial characteristics of phosphorus accumulating organism(PAO) and denitrifying PAO(DPAO) sludge were also analyzed through a quantitative analysis of microbial community structure. Compared with the initial stage of operation characterized by unstable EBPR, both PAO and DPAO SBR produced a stable EBPR performance after about 100-day operation. From day 200 days(DPAO SBR)and 250 days(PAO SBR) onward, sludge granulation was observed, and the average granule size of DPAO SBR was approximately 5 times larger than that of PAO SBR. The DPAO granular sludge contained mainly rod-type microbes, whereas the PAO granular sludge contained coccus-type microbes. Fluorescence in situ hybridization analysis revealed that a high ratio of Accumulibacter clade I was found only in DPAO SBR, revealing the important role of this organism in the denitrifying EBPR system. A pyrosequencing analysis showed that Accumulibacter phosphatis was present in PAO sludge at a high proportion of 6%,whereas it rarely observed in DPAO sludge. Dechloromonas was observed in both PAO sludge(3.3%) and DPAO sludge(3.2%), confirming that this organism can use both O_2 and NO_3^- as electron acceptors. Further, Thauera spp. was identified to have a new possibility as denitrifier capable of phosphorous uptake under anoxic condition.展开更多
文摘旨在分析陶厄氏菌属(Genus Thuaera)中的一株菌株Thauera sp.K11对含酚废水中酚类化合物的降解作用和途径。以石化污水厂分离菌株K11为研究对象,克隆其16S r RNA基因和关键酶基因,并进行系统发育分析,在基因水平探究苯酚降解机理;利用气相色谱技术检测酚类化合物降解效果和苯酚降解机理。结果显示,利用16S r RNA系统学分析发现K11是陶厄氏菌属的一株细菌。该菌对11种酚类化合物具有降解作用,其中5种酚类化合物72 h的降解率>90%。克隆并获得了K11的苯酚羟化酶和邻苯二酚双加氧酶基因。酶活性测定表明,K11通过苯酚羟化酶催化苯酚转化为邻苯二酚,然后利用邻苯二酚-2,3-双加氧酶催化产生2-HMSA。陶厄氏菌Thauera sp.K11是一株能够降解多种酚类化合物的菌株,具有较强的酚类污染物降解能力,其通过苯酚→邻苯二酚→2-HMSA途径进行苯酚降解。
基金supported by the National Natural Science Foundation of China (Nos. 31270166 and 51408580)the Applied Basic Research Program of Sichuan Province (No. 2016JY0078)+1 种基金the Key Laboratory of Environmental and Applied Microbiology Chinese Academy of Sciences (No. KLCAS-2016-05)the Chengdu Science and Technology Project (No. 2015-HM0100550-SF)
文摘To investigate the effect of air-exposed biocathode（AEB） on the performance of singlechamber microbial fuel cell（SCMFC）, wastewater quality, bioelectrochemical characteristics and the electrode biofilms were researched. It was demonstrated that exposing the biocathode to air was beneficial to nitrogen removal and current generation. In Test 1 of 95%AEB, removal rates of ammonia, total nitrogen（TN） and chemical oxygen demand（COD）reached 99.34% ± 0.11%, 99.34% ± 0.10% and 90.79% ± 0.12%, respectively. The nitrogen removal loading rates were 36.38 g N/m3/day. Meanwhile, current density and power density obtained at 0.7 A/m3 and 104 m W/m3 respectively. Further experiments on opencircuit（Test 2） and carbon source（Test 3） indicated that this high performance could be attributed to simultaneous biological nitrification/denitrification and aerobic denitrification, as well as bioelectrochemical denitrification. Results of community analysis demonstrated that both microbial community structures on the surface of the cathode and in the liquid of the chamber were different. The percentage of Thauera, identified as denitrifying bacteria, maintained at a high level of over 50% in water, but decreased gradually in the AEB. Moreover, the genus Nitrosomonas, Alishewanella, Arcobacter and Rheinheimera were significantly enriched in the AEB, which might contribute to both enhancement of nitrogen removal and electricity generation.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education (No.NRF-2015R1D1A1A01061423)
文摘We examined how long-term operation of anaerobic–oxic and anaerobic–anoxic sequencing batch reactors(SBRs) affects the enhanced biological phosphorus removal(EBPR)performance and sludge characteristics. The microbial characteristics of phosphorus accumulating organism(PAO) and denitrifying PAO(DPAO) sludge were also analyzed through a quantitative analysis of microbial community structure. Compared with the initial stage of operation characterized by unstable EBPR, both PAO and DPAO SBR produced a stable EBPR performance after about 100-day operation. From day 200 days(DPAO SBR)and 250 days(PAO SBR) onward, sludge granulation was observed, and the average granule size of DPAO SBR was approximately 5 times larger than that of PAO SBR. The DPAO granular sludge contained mainly rod-type microbes, whereas the PAO granular sludge contained coccus-type microbes. Fluorescence in situ hybridization analysis revealed that a high ratio of Accumulibacter clade I was found only in DPAO SBR, revealing the important role of this organism in the denitrifying EBPR system. A pyrosequencing analysis showed that Accumulibacter phosphatis was present in PAO sludge at a high proportion of 6%,whereas it rarely observed in DPAO sludge. Dechloromonas was observed in both PAO sludge(3.3%) and DPAO sludge(3.2%), confirming that this organism can use both O_2 and NO_3^- as electron acceptors. Further, Thauera spp. was identified to have a new possibility as denitrifier capable of phosphorous uptake under anoxic condition.
