Phytoremediation of methylmercury pollution: merB expression in Arabidopsis thaliana confers resistance to organomercurials
AUTOR(ES)
Bizily, Scott P.
FONTE
The National Academy of Sciences
RESUMO
Methylmercury is an environmental toxicant that biomagnifies and causes severe neurological degeneration in animals. It is produced by bacteria in soils and sediments that have been contaminated with mercury. To explore the potential of plants to extract and detoxify this chemical, we engineered a model plant, Arabidopsis thaliana, to express a modified bacterial gene, merBpe, encoding organomercurial lyase (MerB) under control of a plant promoter. MerB catalyzes the protonolysis of the carbon—mercury bond, removing the organic ligand and releasing Hg(II), a less mobile mercury species. Transgenic plants expressing merBpe grew vigorously on a wide range of concentrations of monomethylmercuric chloride and phenylmercuric acetate. Plants lacking the merBpe gene were severely inhibited or died at the same organomercurial concentrations. Six independently isolated transgenic lines produced merBpe mRNA and MerB protein at levels that varied over a 10- to 15-fold range, and even the lowest levels of merBpe expression conferred resistance to organomercurials. Our work suggests that native macrophytes (e.g., trees, shrubs, grasses) engineered to express merBpe may be used to degrade methylmercury at polluted sites and sequester Hg(II) for later removal.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=21997Documentos Relacionados
- Mercuric ion reduction and resistance in transgenic Arabidopsis thaliana plants expressing a modified bacterial merA gene.
- Research in Air Pollution: Current Trends
- Air pollution: brown skies research.
- Methylmercury Resistance in Desulfovibrio desulfuricans Strains in Relation to Methylmercury Degradation
- WATER POLLUTION: ECONOMIC ASPECTS AND RESEARCH NEEDS