Scorodite (FeAsO_(4)·H_(2)O) is a common arsenic-bearing (As-bearing) iron mineral in nearsurface environments that could immobilize or store As in a bound state.In flooded soils,microbe induced Fe(Ⅲ) or As(Ⅴ) ...Scorodite (FeAsO_(4)·H_(2)O) is a common arsenic-bearing (As-bearing) iron mineral in nearsurface environments that could immobilize or store As in a bound state.In flooded soils,microbe induced Fe(Ⅲ) or As(Ⅴ) reduction can increase the mobility and bioavailability of As.Additionally,humic substances can act as electron shuttles to promote this process.The dynamics of As release and diversity of putative As(Ⅴ)-reducing bacteria during scorodite reduction have yet to be investigated in detail in flooded soils.Here,the microbial reductive dissolution of scorodite was conducted in an flooded soil in the presence of anthraquinone-2,6-disulfonate (AQDS).Anaeromyxobacter,Dechloromonas,Geothrix,Geobacter,Ideonella,and Zoogloea were found to be the dominant indigenous bacteria during Fe(Ⅲ) and As(Ⅴ) reduction.AQDS increased the relative abundance of dominant species,but did not change the diversity and microbial community of the systems with scorodite.Among these bacteria,Geobacter exhibited the greatest increase and was the dominant Fe(Ⅲ)-and As(Ⅴ)-reducing bacteria during the incubation with AQDS and scorodite.AQDS promoted both Fe(Ⅲ) and As(Ⅴ) reduction,and over 80%of released As(Ⅴ) was microbially transformed to As(Ⅲ).The increases in the abundance of arrA gene and putative arrA sequences of Geobacter were higher with AQDS than without AQDS.As a result,the addition of AQDS promoted microbial Fe(Ⅲ) and As(Ⅴ) release and reduction from As-bearing iron minerals into the environment.These results contribute to exploration of the transformation of As from As-bearing iron minerals under anaerobic conditions,thus providing insights into the bioremediation of As-contaminated soil.展开更多
基金supported by the National Science Foundation of China(Nos.41977291 and 42177238)the Science and Technology Foundation of Guangdong,China (Nos.2019A1515011482 and2022A1515011093)+2 种基金the Strategic Priority Research Program (No.XDB40020300)the GDAS’Project of Science and Technology Development (Nos.2019GDASYL-0102002-5 and2020GDASYL-20200103077)Light of West China of Chinese Academy of Sciences。
文摘Scorodite (FeAsO_(4)·H_(2)O) is a common arsenic-bearing (As-bearing) iron mineral in nearsurface environments that could immobilize or store As in a bound state.In flooded soils,microbe induced Fe(Ⅲ) or As(Ⅴ) reduction can increase the mobility and bioavailability of As.Additionally,humic substances can act as electron shuttles to promote this process.The dynamics of As release and diversity of putative As(Ⅴ)-reducing bacteria during scorodite reduction have yet to be investigated in detail in flooded soils.Here,the microbial reductive dissolution of scorodite was conducted in an flooded soil in the presence of anthraquinone-2,6-disulfonate (AQDS).Anaeromyxobacter,Dechloromonas,Geothrix,Geobacter,Ideonella,and Zoogloea were found to be the dominant indigenous bacteria during Fe(Ⅲ) and As(Ⅴ) reduction.AQDS increased the relative abundance of dominant species,but did not change the diversity and microbial community of the systems with scorodite.Among these bacteria,Geobacter exhibited the greatest increase and was the dominant Fe(Ⅲ)-and As(Ⅴ)-reducing bacteria during the incubation with AQDS and scorodite.AQDS promoted both Fe(Ⅲ) and As(Ⅴ) reduction,and over 80%of released As(Ⅴ) was microbially transformed to As(Ⅲ).The increases in the abundance of arrA gene and putative arrA sequences of Geobacter were higher with AQDS than without AQDS.As a result,the addition of AQDS promoted microbial Fe(Ⅲ) and As(Ⅴ) release and reduction from As-bearing iron minerals into the environment.These results contribute to exploration of the transformation of As from As-bearing iron minerals under anaerobic conditions,thus providing insights into the bioremediation of As-contaminated soil.
