The K-segments of the wheat dehydrin DHN-5 are essential for the protection of lactate dehydrogenase and β-glucosidase activities in vitro.
The wheat dehydrin DHN-5 has been previously shown to exhibit heat protecting effect on enzymatic activities. In order to understand the molecular mechanism by which DHN-5 exerts its protective function, we performed an approach to dissect the functional domains of DHN-5 responsible for this feature. In two distinct enzymatic assays, we found that the truncated forms of DHN-5 containing only one K- or two K-segments are able to protect albeit to less extent than the wild type protein, lactate dehydrogenase and β-glucosidase against damage induced by various stresses in vitro. However, the YS- and Φ-segments alone have no protective effects on these enzymes. Therefore, our study provides the evidence that the protective function of DHN-5 seems to be directly linked to its K-segments which through their amphipatic α-helical structure, may act to prevent protein aggregation.
Centre of Biotechnology of Sfax, University of Sfax, Sfax, Tunisia.
Marwa
M
Drira
Walid
W
Saibi
Faïçal
F
Brini
Ali
A
Gargouri
Khaled
K
Masmoudi
Moez
M
Hanin
D007770:L-Lactate Dehydrogenase / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism*; D014908:Triticum / Q000201:enzymology / Q000378:metabolism*; D001617:beta-Glucosidase / Q000378:metabolism*
D010940:Plant Proteins; C070556:dehydrin proteins, plant; D007770:L-Lactate Dehydrogenase; D001617:beta-Glucosidase