title: Arsenic Methylation in Arabidopsis thaliana Expressing an Algal Arsenite Methyltransferase Gene Increases Arsenic Phytotoxicity.
abstract: Arsenic (As) contamination in soil can lead to elevated transfer of As to the food chain. One potential mitigation strategy is to genetically engineer plants to enable them to transform inorganic As to methylated and volatile As species. In this study, we genetically engineered two ecotypes of Arabidopsis thaliana with the arsenite (As(III)) S-adenosylmethyltransferase (arsM) gene from the eukaryotic alga Chlamydomonas reinhardtii. The transgenic A. thaliana plants gained a strong ability to methylate As, converting most of the inorganic As into dimethylarsenate [DMA(V)] in the shoots. Small amounts of volatile As were detected from the transgenic plants. However, the transgenic plants became more sensitive to As(III) in the medium, suggesting that DMA(V) is more phytotoxic than inorganic As. The study demonstrates a negative consequence of engineered As methylation in plants and points to a need for arsM genes with a strong ability to methylate As to volatile species.
authors.affiliation: State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Resources and Environmental Sciences, Nanjing Agricultural University , Nanjing 210095, China.
authors.forename: Zhong
authors.initials: Z
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Resources and Environmental Sciences, Nanjing Agricultural University , Nanjing 210095, China.
authors.forename: Yanling
authors.initials: Y
authors.lastname: Lv
authors.affiliation: State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Resources and Environmental Sciences, Nanjing Agricultural University , Nanjing 210095, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Resources and Environmental Sciences, Nanjing Agricultural University , Nanjing 210095, China.
authors.forename: Wenwen
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Department of Cellular Biology and Pharmacology, Herbert Wertheim College of Medicine, Florida International University , Miami, Florida 33199, United States.
authors.forename: Barry P
authors.initials: BP
authors.lastname: Rosen
authors.affiliation: State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Resources and Environmental Sciences, Nanjing Agricultural University , Nanjing 210095, China.|Rothamsted Research , Harpenden, Hertfordshire AL5 2JQ, United Kingdom.
authors.forename: Fang-Jie
authors.initials: FJ
authors.lastname: Zhao
mesh_terms: D020418:Algal Proteins / Q000235:genetics; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D001151:Arsenic / Q000494:pharmacology*; D018053:Arsenites; D001673:Biodegradation, Environmental; D002101:Cacodylic Acid / Q000032:analysis* / Q000378:metabolism; D016825:Chlamydomonas reinhardtii / Q000235:genetics; D005798:Genes, Bacterial; D008745:Methylation; D008780:Methyltransferases / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000737:chemistry; D030821:Plants, Genetically Modified / Q000235:genetics; D016133:Polymerase Chain Reaction; D012989:Soil Pollutants / Q000032:analysis*
chemical_list: D020418:Algal Proteins; D018053:Arsenites; D012989:Soil Pollutants; D002101:Cacodylic Acid; D008780:Methyltransferases; C116338:arsenite methyltransferase; C015001:arsenite; D001151:Arsenic
keywords: Arabidopsis thaliana; As(III) S-adenosylmethyltransferase; Chlamydomonas reinhardtii; arsenic; arsenic methylation; arsenic speciation; phytotoxicity