title: Mercury and methylmercury detoxification potential by sponge-associated bacteria.
abstract: Ionic and organic forms of mercury (Hg) are powerful cytotoxic and neurotoxic agents in both humans and wild life. The aim of this study was to analyze the resistance profile and potential detoxification of inorganic and organic forms of Hg of bacteria isolated from marine sponges on the coast of Rio de Janeiro, Brazil. Out of the 1,236 colony forming units associated with eleven species of marine sponges, 100 morphologically different bacterial strains were analyzed in this study. Of these, 21 strains were resistant to Hg, 14 of which were classified as highly resistant because they grew despite exposure to 100 µM HgCl2. Fifteen resistant strains reduced Hg and presented merA in their genomes. The remaining six strains produced biosurfactants, suggesting that they may tolerate Hg by sequestration. Eleven strains grew in the presence of methylmercury. Our results suggest a potential for mercury detoxification by marine sponge-associated resistant bacteria, either through reduction or sequestration, as well as the possibility of bioremediation of toxic waste containing mercury.
authors.affiliation: Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho, 373, Cidade Universitária, Rio de Janeiro, 21941-902, Brazil.
authors.forename: Juliana F
authors.initials: JF
authors.lastname: Santos-Gandelman
authors.forename: Marcia
authors.initials: M
authors.lastname: Giambiagi-deMarval
authors.forename: Guilherme
authors.initials: G
authors.lastname: Muricy
authors.forename: Tamar
authors.initials: T
authors.lastname: Barkay
authors.forename: Marinella S
authors.initials: MS
authors.lastname: Laport
mesh_terms: D000818:Animals; D001419:Bacteria / Q000187:drug effects / Q000302:isolation & purification / Q000378:metabolism*; D001711:Biotransformation; D001938:Brazil; D024881:Drug Resistance, Bacterial; D004785:Environmental Pollutants / Q000378:metabolism / Q000633:toxicity; D008627:Mercuric Chloride / Q000378:metabolism* / Q000633:toxicity; D008767:Methylmercury Compounds / Q000378:metabolism* / Q000633:toxicity; D011161:Porifera / Q000382:microbiology*
chemical_list: D004785:Environmental Pollutants; D008767:Methylmercury Compounds; D008627:Mercuric Chloride; C004925:methylmercuric chloride