Article

Overexpression of a pea DNA helicase 45 in bacteria confers salinity stress tolerance.

International Center for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, India.
Plant signaling & behavior 09/2011; 6(9):1271-5. pp.1271-5
Source: PubMed

ABSTRACT Salinity stress is one of the major factors negatively affecting growth and productivity in living organisms including plants and bacteria resulting in significant losses worldwide. Therefore, it would be fruitful to develop salinity stress tolerant useful species and also to understand the mechanism of stress tolerance. The pea DNA helicase 45 (PDH45) is a DNA and RNA helicase, homologous to eukaryotic translation initiation factor 4A (eIF-4A) and is involved in various processes including protein synthesis, maintaining the basic activities of the cell, upregulation of topoisomerase I activity and salinity stress tolerance in plant, but its role in salinity stress tolerance in bacteria has not heretofore been studied. This study provides an evidence for a novel function of the PDH45 gene in high salinity (NaCl) stress tolerance in bacteria (Eschericia coli, BL21 cells) also. Furthermore, it has been shown that the functionally active PDH45 gene is required to show the stress tolerance in bacteria because the single mutants (E183G or R363Q) and the double mutant (E183G + R363Q) of the gene could not confer the same function. The response was specific to Na+ ions as the bacteria could not grow in presence of LiCl. This study suggests that the cellular response to high salinity stress across prokaryotes and plant kingdom is conserved and also helps in our better understanding of mechanism of stress tolerance in bacteria and plants. It could also be very useful in developing high salinity stress tolerant useful bacteria of agronomic importance. Overall, this study provides an evidence for a novel function of the PDH45 gene in high salinity stress tolerance in bacteria.

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Keywords

basic activities
 
BL21 cells
 
cellular response
 
eIF-4A
 
Eschericia coli
 
eukaryotic translation initiation factor 4A
 
functionally active PDH45 gene
 
major factors
 
PDH45 gene
 
pea DNA helicase 45
 
plant kingdom
 
protein synthesis
 
RNA helicase
 
salinity stress
 
salinity stress tolerance
 
salinity stress tolerant useful bacteria
 
salinity stress tolerant useful species
 
single mutants
 
stress tolerance
 
various processes