Quorum sensing(QS)regulation of the composition of ammonia-oxidising archaea(AOA)and ammonia-oxidising bacteria(AOB)communities and functions in wastewater treatment was investigated.Specifically,we explored the role ...Quorum sensing(QS)regulation of the composition of ammonia-oxidising archaea(AOA)and ammonia-oxidising bacteria(AOB)communities and functions in wastewater treatment was investigated.Specifically,we explored the role of N-acyl-L-homoserine lactones(AHLs)in microbial community dynamics in activated sludge.On average,the specific ammoniaoxidising-rate increased from 1.6 to 2.8 mg NH_4^+-N/g MLSS/hr after treatment with long-chain AHLs for 16 days,and the addition of AHLs to sludge resulted in an increased number of AOA/AOB amoA genes.Significant differences were observed in the AOA communities of control and AHL-treated cultures,but not the AOB community.Furthermore,the dominant functional AOA strains of the Crenarchaeota altered their ecological niche in response to AHL addition.These results provide evidence that AHLs play an important role in mediating AOA/AOB microbial community parameters and demonstrate the potential for application of QS to the regulation of nitrogen compound metabolism in wastewater treatment.展开更多
Two rice cultivars(Xiushui 09 and Chunyou 84)were used to evaluate the effects of various soil oxygen(O2)conditions on soil nitrogen(N)transformation,absorption and accumulation in rice plants.The treatments were cont...Two rice cultivars(Xiushui 09 and Chunyou 84)were used to evaluate the effects of various soil oxygen(O2)conditions on soil nitrogen(N)transformation,absorption and accumulation in rice plants.The treatments were continuous flooding(CF),continuous flooding and aeration(CFA),and alternate wetting and drying(AWD).The results showed that the AWD and CFA treatments improved soil N transformation,rice growth,and N absorption and accumulation.Soil NO3–content,nitrification activity and ammonia-oxidising bacteria abundance,leaf area,nitrate reductase activity,and N absorption and accumulation in rice all increased in both cultivars.However,soil microbial biomass carbon and pH did not significantly change during the whole period of rice growth.Correlation analysis revealed a significant positive correlation between the nitrification activity and ammonia-oxidising bacteria abundance,and both of them significantly increased as the total N accumulation in rice increased.Our results indicated that improved soil O2 conditions led to changing soil N cycling and contributed to increases in N absorption and accumulation by rice in paddy fields.展开更多
基金supported by the National Natural Science Foundation of China (No. 41501250)the Strategic Priority Research Program of the Chinese Academy of Sciences (No. XDB15030101)the National Key Research and Development Program of China (Nos. 2016YFC0500401 and 2017YFC050580301)
文摘Quorum sensing(QS)regulation of the composition of ammonia-oxidising archaea(AOA)and ammonia-oxidising bacteria(AOB)communities and functions in wastewater treatment was investigated.Specifically,we explored the role of N-acyl-L-homoserine lactones(AHLs)in microbial community dynamics in activated sludge.On average,the specific ammoniaoxidising-rate increased from 1.6 to 2.8 mg NH_4^+-N/g MLSS/hr after treatment with long-chain AHLs for 16 days,and the addition of AHLs to sludge resulted in an increased number of AOA/AOB amoA genes.Significant differences were observed in the AOA communities of control and AHL-treated cultures,but not the AOB community.Furthermore,the dominant functional AOA strains of the Crenarchaeota altered their ecological niche in response to AHL addition.These results provide evidence that AHLs play an important role in mediating AOA/AOB microbial community parameters and demonstrate the potential for application of QS to the regulation of nitrogen compound metabolism in wastewater treatment.
基金the National Key Research and Development Program of China(Grant No.2016YFD300507)the National Natural Science Foundation of China(Grant No.31401343)the National Rice Industry Technology System of China(Grant No.CARS-01-04A).
文摘Two rice cultivars(Xiushui 09 and Chunyou 84)were used to evaluate the effects of various soil oxygen(O2)conditions on soil nitrogen(N)transformation,absorption and accumulation in rice plants.The treatments were continuous flooding(CF),continuous flooding and aeration(CFA),and alternate wetting and drying(AWD).The results showed that the AWD and CFA treatments improved soil N transformation,rice growth,and N absorption and accumulation.Soil NO3–content,nitrification activity and ammonia-oxidising bacteria abundance,leaf area,nitrate reductase activity,and N absorption and accumulation in rice all increased in both cultivars.However,soil microbial biomass carbon and pH did not significantly change during the whole period of rice growth.Correlation analysis revealed a significant positive correlation between the nitrification activity and ammonia-oxidising bacteria abundance,and both of them significantly increased as the total N accumulation in rice increased.Our results indicated that improved soil O2 conditions led to changing soil N cycling and contributed to increases in N absorption and accumulation by rice in paddy fields.
