Journal
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
Volume 87, Issue 23, Pages -Publisher
AMER SOC MICROBIOLOGY
DOI: 10.1128/AEM.01769-21
Keywords
DNA-stable isotope probing; metagenomic binning; As(III)-oxidizing bacteria; arsenic-contaminated water; biological As(III) oxidation
Categories
Funding
- National Natural Science Foundation of China [42007357, 41771301]
- China Postdoctoral Science Foundation [2020T130127]
- Science and Technology Planning Project of Guangzhou [202002030271, 202002020072]
- Guangdong Basic and Applied Basic Research Foundation [2019A1515110351]
- GDAS Project of Science and Technology Development [2020GDASYL-20200102014]
Ask authors/readers for more resources
This study investigated the potential of biological arsenite oxidation in wastewater treatment facilities and identified putative AOB responsible for this process through DNA-SIP and metagenomic binning. Functional genes encoding As resistance, As(III) oxidation, denitrification, and carbon fixation were found in the MAGs associated with these AOB, indicating their metabolic potentials. The presence of genes related to secondary metabolite biosynthesis and extracellular polymeric substance metabolism may enhance the capacity of these AOB for As(III) oxidation in activated sludge.
Biological arsenite [As(III)] oxidation is an important process in the removal of toxic arsenic (As) from contaminated water. However, the diversity and metabolic potentials of As(III)-oxidizing bacteria (AOB) responsible for As(III) oxidation in wastewater treatment facilities are not well documented. In this study, two groups of bioreactors inoculated with activated sludge were operated under anoxic or oxic conditions to treat As-containing synthetic wastewater. Batch tests of inoculated sludges from the bioreactors further indicated that microorganisms could use nitrate or oxygen as electron acceptors to stimulate biological As(III) oxidation, suggesting the potentials of this process in wastewater treatment facilities. In addition, DNA-based stable isotope probing (DNA-SIP) was performed to identify the putative AOB in the activated sludge. Bacteria associated with Thiobacillus were identified as nitrate-dependent AOB, while bacteria associated with Hydrogenophaga were identified as aerobic AOB in activated sludge. Metagenomic binning reconstructed a number of high-quality metagenome-assembled genomes (MAGs) associated with the putative AOB. Functional genes encoding As resistance, As(III) oxidation, denitrification, and carbon fixation were identified in these MAGs, suggesting their potentials for chemoautotrophic As(III) oxidation. In addition, the presence of genes encoding secondary metabolite biosynthesis and extracellular polymeric substance metabolism in these MAGs may facilitate the proliferation of these AOB in activated sludge and enhance their capacity for As(III) oxidation. IMPORTANCE AOB play an important role in the removal of toxic arsenic from wastewater. Most of the AOB have been isolated from natural environments. However, knowledge regarding the structure and functional roles of As(III)-oxidizing communities in wastewater treatment facilities is not well documented. The combination of DNA-SIP and metagenomic binning provides an opportunity to elucidate the diversity of in situ AOB community inhabiting the activated sludges. In this study, the putative AOB responsible for As(III) oxidation in wastewater treatment facilities were identified, and their metabolic potentials, including As(III) oxidation, denitrification, carbon fixation, secondary metabolite biosynthesis, and extracellular polymeric substance metabolism, were investigated. This observation provides an understanding of anoxic and/or oxic AOB during the As(III) oxidation process in wastewater treatment facilities, which may contribute to the removal of As from contaminated water.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available