Prevalence of Methylated Arsenic and Microbial Arsenic Methylation Genes in Paddy Soils of the Mekong Delta

Qiao，Jiangtao1,2; Liu，Jingyu3,4,5,6; Palomo，Alejandro3,4,5; Bostick，Benjamin C.7; Phan，Kongkea8; Zheng，Yan3,4,5; Li，Fangbai1,2

2023-07-04

10.1021/acs.est.3c00210

Environmental Science and Technology   Impact Factor & Quartile

0013-936X

1520-5851

Microbially mediated inorganic-methylated arsenic (As) transformation in paddy soil is crucial to rice safety; however, the linkages between the microbial As methylation process and methylated As species remain elusive. Here, 62 paddy soils were collected from the Mekong River delta of Cambodia to profile As-related functional gene composition involved in the As cycle. The soil As concentration ranged from <1 to 16.6 mg kg, with average As contents of approximately 81% as methylated As and 54% as monomethylarsenate (MMAs(V)) in the phosphate- and oxalate-extractable fractions based on As sequential extraction analysis. Quantitative PCR revealed high arsenite-methylating gene (arsM) copy numbers, and metagenomics identified consistently high arsM gene abundance. The abundance of As-related genes was the highest in bacteria, followed by archaea and fungi. Pseudomonas, Bradyrhizobium, Burkholderia, and Anaeromyxobacter were identified as bacteria harboring the most genes related to As biotransformation. Moreover, arsM and arsI (As demethylation) gene-containing operons were identified in the metagenome-assembled genomes (MAGs), implying that arsM and arsI could be transcribed together. The prevalence of methylated As and arsM genes may have been overlooked in tropical paddy fields. The As methylation-demethylation cycle should be considered when manipulating the methylated As pool in paddy fields for rice safety.

arsenic methylation metagenomics microbial community paddy soil

SCI

English

NI Journal Papers ; NI论文

Corresponding

National Science Foundation[42030702];

Engineering ; Environmental Sciences & Ecology

Engineering, Environmental ; Environmental Sciences

WOS:001018767500001

AMER CHEMICAL SOC

ENVIRONMENT/ECOLOGY

2-s2.0-85164209224

Scopus

1.Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management,Institute of Eco-environmental and Soil Sciences,Guangdong Academy of Sciences,Guangzhou,Guangdong,510650,China
2.National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China,Guangzhou,Guangdong,510650,China
3.State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control,School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,Guangdong,518055,China
4.Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control,School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,Guangdong,518055,China
5.Shenzhen Key Laboratory of Marine Archaea Geo-Omics,Department of Ocean Science and Engineering,Southern University of Science and Technology,Shenzhen,Guangdong,518055,China
6.Queensland Alliance for Environmental Health Science (QAEHS),The University of Queensl,Brisbane,4108,Australia
7.Lamont-Doherty Earth Observatory,Columbia University,Palisades,10964,United States
8.Faculty of Science and Technology,International University,Phnom Penh,12101,Cambodia

Qiao，Jiangtao,Liu，Jingyu,Palomo，Alejandro,et al. Prevalence of Methylated Arsenic and Microbial Arsenic Methylation Genes in Paddy Soils of the Mekong Delta[J]. Environmental Science and Technology,2023,57(26):9675-9682.

Qiao，Jiangtao.,Liu，Jingyu.,Palomo，Alejandro.,Bostick，Benjamin C..,Phan，Kongkea.,...&Li，Fangbai.(2023).Prevalence of Methylated Arsenic and Microbial Arsenic Methylation Genes in Paddy Soils of the Mekong Delta.Environmental Science and Technology,57(26),9675-9682.

Qiao，Jiangtao,et al."Prevalence of Methylated Arsenic and Microbial Arsenic Methylation Genes in Paddy Soils of the Mekong Delta".Environmental Science and Technology 57.26(2023):9675-9682.