title: Toward Bioremediation of Methylmercury Using Silica Encapsulated Escherichia coli Harboring the mer Operon.
abstract: Mercury is a highly toxic heavy metal and the ability of the neurotoxin methylmercury to biomagnify in the food chain is a serious concern for both public and environmental health globally. Because thousands of tons of mercury are released into the environment each year, remediation strategies are urgently needed and prompted this study. To facilitate remediation of both organic and inorganic forms of mercury, Escherichia coli was engineered to harbor a subset of genes (merRTPAB) from the mercury resistance operon. Protein products of the mer operon enable transport of mercury into the cell, cleavage of organic C-Hg bonds, and subsequent reduction of ionic mercury to the less toxic elemental form, Hg(0). E. coli containing merRTPAB was then encapsulated in silica beads resulting in a biological-based filtration material. Performing encapsulation in aerated mineral oil yielded silica beads that were smooth, spherical, and similar in diameter. Following encapsulation, E. coli containing merRTPAB retained the ability to degrade methylmercury and performed similarly to non-encapsulated cells. Due to the versatility of both the engineered mercury resistant strain and silica bead technology, this study provides a strong foundation for use of the resulting biological-based filtration material for methylmercury remediation.
authors.affiliation: BioTechnology Institute, University of Minnesota-Twin Cities, St. Paul, Minnesota, United States of America.|Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota-Twin Cities, Minneapolis, Minnesota, United States of America.
authors.forename: Aunica L
authors.initials: AL
authors.lastname: Kane
authors.affiliation: BioTechnology Institute, University of Minnesota-Twin Cities, St. Paul, Minnesota, United States of America.
authors.forename: Basem
authors.initials: B
authors.lastname: Al-Shayeb
authors.affiliation: BioTechnology Institute, University of Minnesota-Twin Cities, St. Paul, Minnesota, United States of America.
authors.forename: Patrick V
authors.initials: PV
authors.lastname: Holec
authors.affiliation: BioTechnology Institute, University of Minnesota-Twin Cities, St. Paul, Minnesota, United States of America.
authors.forename: Srijay
authors.initials: S
authors.lastname: Rajan
authors.affiliation: BioTechnology Institute, University of Minnesota-Twin Cities, St. Paul, Minnesota, United States of America.
authors.forename: Nicholas E
authors.initials: NE
authors.lastname: Le Mieux
authors.affiliation: BioTechnology Institute, University of Minnesota-Twin Cities, St. Paul, Minnesota, United States of America.
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Heinsch
authors.affiliation: Department of Soil, Water, and Climate, University of Minnesota-Twin Cities, St. Paul, Minnesota, United States of America.
authors.forename: Sona
authors.initials: S
authors.lastname: Psarska
authors.affiliation: BioTechnology Institute, University of Minnesota-Twin Cities, St. Paul, Minnesota, United States of America.
authors.forename: Kelly G
authors.initials: KG
authors.lastname: Aukema
authors.affiliation: BioTechnology Institute, University of Minnesota-Twin Cities, St. Paul, Minnesota, United States of America.|Department of Biomedical Engineering, University of Minnesota-Twin Cities, Minneapolis, Minnesota, United States of America.
authors.forename: Casim A
authors.initials: CA
authors.lastname: Sarkar
authors.affiliation: Department of Soil, Water, and Climate, University of Minnesota-Twin Cities, St. Paul, Minnesota, United States of America.
authors.forename: Edward A
authors.initials: EA
authors.lastname: Nater
authors.affiliation: BioTechnology Institute, University of Minnesota-Twin Cities, St. Paul, Minnesota, United States of America.|Department of Microbiology and Immunology, University of Minnesota-Twin Cities, Minneapolis, Minnesota, United States of America.
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Gralnick
mesh_terms: D001673:Biodegradation, Environmental; D052978:Disk Diffusion Antimicrobial Tests; D019008:Drug Resistance, Neoplasm; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism*; D008767:Methylmercury Compounds / Q000378:metabolism* / Q000494:pharmacology; D008863:Microspheres; D009876:Operon; D012822:Silicon Dioxide
chemical_list: D008767:Methylmercury Compounds; D012822:Silicon Dioxide