Efficient purification of cryoprotective dehydrin protein from the radish (Raphanus sativus) taproot

Dehydrin is a protein that is related to cold stress tolerance in plants. Because dehydrin shows potent cryoprotective activity, it has the potential to be used in food storage applications. In this paper, we presented an efficient purification method for native dehydrin from radishes (Raphanus sativus). Immunoblot analysis using an anti-Arabidopsis KS-type dehydrin antibody revealed that the related dehydrin accumulates in the radish taproot. The radish dehydrin that accumulated in the vascular tissues of the taproot was purified through two simple chromatographic steps: immobilized metal affinity chromatography followed by anion exchange chromatography. The yield was higher than yields previously reported on a fresh weight basis. The cryoprotective activity for malate dehydrogenase shown by purified dehydrin was more potent than that shown by small molecule cryoprotectants. This suggests that the radish is an appropriate source for the production of native dehydrin.