Shewanella sp. ANA-3 with the respiratory arsenate reductase(ArrAB) and MR-1 with ferric reduction ability always coexist in the presence of high arsenic(As)-containing waste residue. However, their synergistic impact...Shewanella sp. ANA-3 with the respiratory arsenate reductase(ArrAB) and MR-1 with ferric reduction ability always coexist in the presence of high arsenic(As)-containing waste residue. However, their synergistic impacts on As transformation and mobility remain unclear. To identify which bacterium, ANA-3 or MR-1, dominates As mobility in the coexisting environment, we explored the As biotransformation in the industrial waste residue in the presence of Shewanella sp. ANA-3 and MR-1. The incubation results show that As(Ⅲ)was the main soluble species, and strain ANA-3 dominated As mobilization. The impact of ANA-3 was weakened by MR-1, probably due to the survival competition between these two bacteria. The results of micro X-ray fluorescence and X-ray photoelectron spectroscopy analyses further reveal the pathway for ANA-3 to enhance As mobility. Strain ANA-3 almost reduced 100% surface-bound Fe(Ⅲ), and consequently led to As(V) release. The dissolved As(V) was then reduced to As(Ⅲ) by ANA-3. The results of this study help to understand the fate of arsenic in the subsurface and highlight the importance of the safe disposal of high As-containing industrial waste.展开更多
基金supported by the National Natural Science Foundation of China (Nos. 41877378 and 41425016)the China Postdoctoral Science Foundation (No. 2021M691924)the Shandong Province Natural Science Foundation of Major Basic Research Program, China (No. ZR2020ZD34)。
文摘Shewanella sp. ANA-3 with the respiratory arsenate reductase(ArrAB) and MR-1 with ferric reduction ability always coexist in the presence of high arsenic(As)-containing waste residue. However, their synergistic impacts on As transformation and mobility remain unclear. To identify which bacterium, ANA-3 or MR-1, dominates As mobility in the coexisting environment, we explored the As biotransformation in the industrial waste residue in the presence of Shewanella sp. ANA-3 and MR-1. The incubation results show that As(Ⅲ)was the main soluble species, and strain ANA-3 dominated As mobilization. The impact of ANA-3 was weakened by MR-1, probably due to the survival competition between these two bacteria. The results of micro X-ray fluorescence and X-ray photoelectron spectroscopy analyses further reveal the pathway for ANA-3 to enhance As mobility. Strain ANA-3 almost reduced 100% surface-bound Fe(Ⅲ), and consequently led to As(V) release. The dissolved As(V) was then reduced to As(Ⅲ) by ANA-3. The results of this study help to understand the fate of arsenic in the subsurface and highlight the importance of the safe disposal of high As-containing industrial waste.
