Purification, characterization and partial cDNA cloning of high-temperature stress-induced protein from French bean (Phaseolus vulgaris)

In order to identify the components of high temperature response in French bean, three heat shock proteins induced under high temperature were purified to homogeneity by Carboxy methyl cellulose and sephadex G-100 chromatography followed by preparative SDS-PAGE. Two of these, Hsp1 and Hsp3 were further characterized by immuno-detection with polyclonal antibodies. Hsp3 exhibited ATPase and chaperone activity with malate dehydrogenase and citrate synthase. Partial cDNA for Hsp3 synthesized using the primer derived from amino-terminal sequence was cloned and expressed in Escherichia coli. The recombinant protein possesses ATPase activity, and showed thermal protection at 50°C in Escherichia coli. The translated partial cDNA showed homology with stress induced proteins including ATPases from higher plants. These results supported the fact that French bean response to high temperature stress involves Hsps as one of the principal components.