As one of the transition metals, vanadium（V）（V（V）） in trace amounts represents an essential element for normal cell growth, but becomes toxic when its concentration is above 1 mg/L. V（V） can alter cellular dif...As one of the transition metals, vanadium（V）（V（V）） in trace amounts represents an essential element for normal cell growth, but becomes toxic when its concentration is above 1 mg/L. V（V） can alter cellular differentiation, gene expression, and other biochemical and metabolic phenomena. A feasible method to detoxify V（V） is to reduce it to V（IV）, which precipitates and can be readily removed from the water. The bioreduction of V（V） in a contaminated groundwater was investigated using autohydrogentrophic bacteria and hydrogen gas as the electron donor. Compared with the previous organic donors,H2 shows the advantages as an ideal electron donor, including nontoxicity and less production of excess biomass. V（V） was 95.5% removed by biochemical reduction when autohydrogentrophic bacteria and hydrogen were both present, and the reduced V（IV）precipitated, leading to total-V removal. Reduction kinetics could be described by a first-order model and were sensitive to p H and temperature, with the optimum ranges of p H 7.5–8.0 and 35–40°C, respectively. Phylogenetic analysis by clone library showed that the dominant species in the experiments with V（V） bioreduction belonged to theβ-Proteobacteria. Previously known V（V）-reducing species were absent, suggesting that V（V）reduction was carried out by novel species. Their selective enrichment during V（V）bioreduction suggests that Rhodocyclus, a denitrifying bacterium, and Clostridium, a fermenter known to carry out metal reduction, were responsible for V（V） bioreduction.展开更多
Soil microorganisms play globally vital roles in the environment,ecology,and agriculture[1],and have become a research hotspot.Most research in these fields depends on microbial sequencing and analysis[2,3],which shou...Soil microorganisms play globally vital roles in the environment,ecology,and agriculture[1],and have become a research hotspot.Most research in these fields depends on microbial sequencing and analysis[2,3],which should ideally be conducted immediately after sample collection[4].However on-site DNA extraction and sequencing are often impractical.Therefore,freshly collected soil samples must be properly stored for transport before sequencing.While this sounds like a natural operation,proper transport of soil samples has been widely overlooked,challenging the accuracy of all related research.展开更多
The nitrogen cycle plays a vital role in sustaining productive and healthy ecosystems,with the microbial nitrogen cycle being a focal point in agriculture and eco-environmental protection.Among these microbially media...The nitrogen cycle plays a vital role in sustaining productive and healthy ecosystems,with the microbial nitrogen cycle being a focal point in agriculture and eco-environmental protection.Among these microbially mediated processes is ammonium(NH_(4)^(+))oxidation,the gatekeeper of the nitrogen cycle.Our understanding of ammonium oxidation is continuously evolving,thanks to recent research breakthroughs like comammox,Feammox,and dirammox[1-6].The increasing complexity of ammonium oxidation necessitates more precise and well-focused research tools beyond those commonly used today.展开更多
River waters in China have dual contamination by nutrients and recalcitrant organic compounds. In principle, the organic compotmds could be used to drive denitrification of nitrate, thus arresting eutrophication poten...River waters in China have dual contamination by nutrients and recalcitrant organic compounds. In principle, the organic compotmds could be used to drive denitrification of nitrate, thus arresting eutrophication potential, if the recalcitrant organics could be made bioavailable. This study investigated the potential to make the recalcitrant organics bioavailable through photocatalysis. Batch denitrification tests in a biofilm reactor demonstrated that dual-contaminated river water was short of available electron donor, which resulted in low total nitrogen （TN） removal by denitrification. However, the denitrification rate was increased signifi- cantly by adding glucose or by making the organic matters of the river water more bioavailable through photocata- lysis. Photocatalysis for 15 min increased the Chemical Oxygen Demand （COD） of the river water from 53 to 84 mg. L-1 and led to a 4-fold increase in TN removal. The increase in TN removal gave the same effect as adding 92 mg.L 1 of glucose. During the photocatalysis experi- ments, the COD increased because photocatalysis trans- formed organic molecules from those that are resistant to dichromate oxidation in the COD test to those that can be oxidized by dichromate. This phenomenon was verified by testing photocatalysis of pyridine added to the river water. These findings point to the potential for N removal via denitrification after photocatalysis, and they also suggest that the rivers in China may be far more polluted than indicated by COD assays.展开更多
Perry L.McCarty passed away on June 4,at the age of 91.He was a revered leader in Environmental Engineering and Biotechnology.Dr.Perry L.McCarty passed away peacefully and with his family on June 4,2023.Perry was a wo...Perry L.McCarty passed away on June 4,at the age of 91.He was a revered leader in Environmental Engineering and Biotechnology.Dr.Perry L.McCarty passed away peacefully and with his family on June 4,2023.Perry was a world leader in Environmental Engineering,with special emphasis on Environmental Biotechnology,in which we form partnerships with microbial communities that provide services to make human society more sustainable.I was one of Perry’s Ph.D.students,and we worked together on research,service,and publishing throughout my career.I have deep and personal knowledge of how Perry and his students developed the fundamental principles that have allowed Environmental Biotechnology to flourish and advance humans’sustainability.展开更多
基金supported by the National Natural Science Foundation of China (No. 51378368)
文摘As one of the transition metals, vanadium（V）（V（V）） in trace amounts represents an essential element for normal cell growth, but becomes toxic when its concentration is above 1 mg/L. V（V） can alter cellular differentiation, gene expression, and other biochemical and metabolic phenomena. A feasible method to detoxify V（V） is to reduce it to V（IV）, which precipitates and can be readily removed from the water. The bioreduction of V（V） in a contaminated groundwater was investigated using autohydrogentrophic bacteria and hydrogen gas as the electron donor. Compared with the previous organic donors,H2 shows the advantages as an ideal electron donor, including nontoxicity and less production of excess biomass. V（V） was 95.5% removed by biochemical reduction when autohydrogentrophic bacteria and hydrogen were both present, and the reduced V（IV）precipitated, leading to total-V removal. Reduction kinetics could be described by a first-order model and were sensitive to p H and temperature, with the optimum ranges of p H 7.5–8.0 and 35–40°C, respectively. Phylogenetic analysis by clone library showed that the dominant species in the experiments with V（V） bioreduction belonged to theβ-Proteobacteria. Previously known V（V）-reducing species were absent, suggesting that V（V）reduction was carried out by novel species. Their selective enrichment during V（V）bioreduction suggests that Rhodocyclus, a denitrifying bacterium, and Clostridium, a fermenter known to carry out metal reduction, were responsible for V（V） bioreduction.
基金supported by the National Natural Science Foundation of China(42320104002)the Jiangsu Agriculture Science and Technology Innovation Fund(JASTIF,CX(22)1003)the Original Innovation Project of Chinese Academy of Sciences(ZDBS-LY-DQC024)。
文摘Soil microorganisms play globally vital roles in the environment,ecology,and agriculture[1],and have become a research hotspot.Most research in these fields depends on microbial sequencing and analysis[2,3],which should ideally be conducted immediately after sample collection[4].However on-site DNA extraction and sequencing are often impractical.Therefore,freshly collected soil samples must be properly stored for transport before sequencing.While this sounds like a natural operation,proper transport of soil samples has been widely overlooked,challenging the accuracy of all related research.
基金supported by the National Natural Science Foundation of China(41825021 and 42320104002)the Natural Science Foundation of Jiangsu Province(BE2020731)+1 种基金the Jiangsu Agriculture Science and Technology Innovation Fund(JASTIF,CX(22)1003)the Original Innovation Project of Chinese Academy of Sciences(ZDBS-LY-DQC024)。
文摘The nitrogen cycle plays a vital role in sustaining productive and healthy ecosystems,with the microbial nitrogen cycle being a focal point in agriculture and eco-environmental protection.Among these microbially mediated processes is ammonium(NH_(4)^(+))oxidation,the gatekeeper of the nitrogen cycle.Our understanding of ammonium oxidation is continuously evolving,thanks to recent research breakthroughs like comammox,Feammox,and dirammox[1-6].The increasing complexity of ammonium oxidation necessitates more precise and well-focused research tools beyond those commonly used today.
基金Acknowledgements The authors acknowledge the financial support by the National Natural Science Foundation of China （Grant Nos. 50978164 and 50678102）, the Major Science and Technology Program for Water Pollution Control and Treatment （No. 2009ZX07313-003）, the Innovation Fund for Key Projects of Shanghai Municipal Education Commission （No. 10ZZ82）, the Special Foundation of Chinese Colleges and Universities Doctoral Discipline （Nos. 20113127110002 and 20070270003）, the Shanghai Leading Academic Discipline Project （No. S30406）, and the United States National Science Foundation （No. 0651794）.
文摘River waters in China have dual contamination by nutrients and recalcitrant organic compounds. In principle, the organic compotmds could be used to drive denitrification of nitrate, thus arresting eutrophication potential, if the recalcitrant organics could be made bioavailable. This study investigated the potential to make the recalcitrant organics bioavailable through photocatalysis. Batch denitrification tests in a biofilm reactor demonstrated that dual-contaminated river water was short of available electron donor, which resulted in low total nitrogen （TN） removal by denitrification. However, the denitrification rate was increased signifi- cantly by adding glucose or by making the organic matters of the river water more bioavailable through photocata- lysis. Photocatalysis for 15 min increased the Chemical Oxygen Demand （COD） of the river water from 53 to 84 mg. L-1 and led to a 4-fold increase in TN removal. The increase in TN removal gave the same effect as adding 92 mg.L 1 of glucose. During the photocatalysis experi- ments, the COD increased because photocatalysis trans- formed organic molecules from those that are resistant to dichromate oxidation in the COD test to those that can be oxidized by dichromate. This phenomenon was verified by testing photocatalysis of pyridine added to the river water. These findings point to the potential for N removal via denitrification after photocatalysis, and they also suggest that the rivers in China may be far more polluted than indicated by COD assays.
文摘Perry L.McCarty passed away on June 4,at the age of 91.He was a revered leader in Environmental Engineering and Biotechnology.Dr.Perry L.McCarty passed away peacefully and with his family on June 4,2023.Perry was a world leader in Environmental Engineering,with special emphasis on Environmental Biotechnology,in which we form partnerships with microbial communities that provide services to make human society more sustainable.I was one of Perry’s Ph.D.students,and we worked together on research,service,and publishing throughout my career.I have deep and personal knowledge of how Perry and his students developed the fundamental principles that have allowed Environmental Biotechnology to flourish and advance humans’sustainability.
