title: Expression of Echmr gene from Eichhornia offers multiple stress tolerance to Cd sensitive Escherichia coli Δgsh mutants.
abstract: The detoxification of heavy metals frequently involves conjugation to glutathione prior to compartmentalization and eflux in higher plants. We have expressed a heavy metal stress responsive (Echmr) gene from water hyacinth, which conferred tolerance to Cd sensitive Escherichia coli Δgsh mutants against heavy metals and abiotic stresses. The recombinant E. coli Δgsh mutant cells showed better growth recovery and survival than control cells under Cd (200 μM), Pb(200 μM), heat shock (50 °C), cold stress at 4 °C for 4 h, and UV-B (20 min) exposure. The enhanced expression of Echmr gene revealed by northern analysis during above stresses further advocates its role in multi-stress tolerance. Heterologous expression of EcHMR from Eichhornia rescued Cd(2+) sensitive E. coli mutants from Cd(2+) toxicity and induced better recovery post abiotic stresses. This may suggests a possible role of Echmr in Cd(II) and desiccation tolerance in plants for enhanced stress response.
authors.affiliation: Department of Biotechnology, Indian Institute of Technology Guwahati, North Guwahati 781039, Assam, India; Earth Institute, Molecular Plant Pathogen Interactions Group, School of Biology and Environmental Science, University College Dublin, Ireland. Electronic address: g.thapa@alumni.iitg.ernet.in.
authors.forename: G
authors.initials: G
authors.lastname: Thapa
authors.affiliation: Utrecht University, The Netherlands.
authors.forename: D
authors.initials: D
authors.lastname: Das
authors.affiliation: Earth Institute, Molecular Plant Pathogen Interactions Group, School of Biology and Environmental Science, University College Dublin, Ireland.
authors.forename: L R
authors.initials: LR
authors.lastname: Gunupuru
mesh_terms: D002104:Cadmium / Q000378:metabolism / Q000633:toxicity*; D003001:Cloning, Molecular; D031806:Eichhornia / Q000235:genetics* / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D015870:Gene Expression; D017343:Genes, Plant; D010165:Palladium / Q000378:metabolism / Q000633:toxicity; D010940:Plant Proteins / Q000235:genetics; D013312:Stress, Physiological
chemical_list: D010940:Plant Proteins; D002104:Cadmium; D010165:Palladium
keywords: Cadmium (Cd); Eichhornia; Glutathione (GSH); Heavy metal (HM); Reactive oxygen species (ROS); Stress responsive