Biochemical and Biophysical Research Communications, Vol.478, No.1, 101-109, 2016
Expression of Echmr gene from Eichhornia offers multiple stress tolerance to Cd sensitive Escherichia coli Delta gsh mutants
The detoxification of heavy metals frequently involves conjugation to glutathione prior to compart-mentalization 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 Delta gsh mutants against heavy metals and abiotic stresses. The recombinant E. coli Delta gsh mutant cells showed better growth recovery and survival than control cells under Cd (200 mu M), Pb(200 mu M), heat shock (50 degrees C), cold stress at 4 degrees 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 Cd2+ sensitive E. coli mutants from Cd2+ 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. (C) 2016 Elsevier Inc. All rights reserved.