title: Genetically Engineering Bacillus subtilis with a Heat-Resistant Arsenite Methyltransferase for Bioremediation of Arsenic-Contaminated Organic Waste.
abstract: Organic manures may contain high levels of arsenic (As) due to the use of As-containing growth-promoting substances in animal feed. To develop a bioremediation strategy to remove As from organic waste, Bacillus subtilis 168, a bacterial strain which can grow at high temperature but is unable to methylate and volatilize As, was genetically engineered to express the arsenite S-adenosylmethionine methyltransferase gene (CmarsM) from the thermophilic alga Cyanidioschyzon merolae. The genetically engineered B. subtilis 168 converted most of the inorganic As in the medium into dimethylarsenate and trimethylarsine oxide within 48 h and volatized substantial amounts of dimethylarsine and trimethylarsine. The rate of As methylation and volatilization increased with temperature from 37 to 50°C. When inoculated into an As-contaminated organic manure composted at 50°C, the modified strain significantly enhanced As volatilization. This study provides a proof of concept of using genetically engineered microorganisms for bioremediation of As-contaminated organic waste during composting.
authors.affiliation: Jiangsu Key Laboratory for Organic Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Huang
authors.affiliation: Jiangsu Key Laboratory for Organic Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China.
authors.forename: Chuan
authors.initials: C
authors.lastname: Chen
authors.affiliation: Jiangsu Key Laboratory for Organic Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China.
authors.forename: Qirong
authors.initials: Q
authors.lastname: Shen
authors.affiliation: Department of Cellular Biology and Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, Florida, USA.
authors.forename: Barry P
authors.initials: BP
authors.lastname: Rosen
authors.affiliation: Jiangsu Key Laboratory for Organic Waste Utilization, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, China Rothamsted Research, Harpenden, Hertfordshire, United Kingdom Fangjie.Zhao@njau.edu.cn.
authors.forename: Fang-Jie
authors.identifier: http://orcid.org/0000-0002-0164-169X
authors.initials: FJ
authors.lastname: Zhao
mesh_terms: D001151:Arsenic / Q000378:metabolism*; D001412:Bacillus subtilis / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D001673:Biodegradation, Environmental; D004795:Enzyme Stability; D006358:Hot Temperature; D008780:Methyltransferases / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D015202:Protein Engineering; D012989:Soil Pollutants / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D012989:Soil Pollutants; D008780:Methyltransferases; C116338:arsenite methyltransferase; D001151:Arsenic