Expression, subcellular localization, and enzyme activity of a recombinant human extra-cellular superoxide dismutase in tobacco (Nicotiana benthamiana L.).
Human extracellular superoxide dismutase (hEC-SOD) is an enzyme that scavenges reactive oxygen species (ROS). Because of its antioxidant activity, hEC-SOD has been used as a therapeutic protein to treat skin disease and arthritis in mammalian systems. In this study, codon-optimized hEC-SOD was expressed in tobacco (Nicotiana benthamiana L.) via a plant-based transient protein expression system. Plant expression binary vectors containing full-length hEC-SOD (f-hEC-SOD) and modified hEC-SOD (m-hEC-SOD), in which the signal peptide and heparin-binding domain were deleted, were constructed for the cytosolic-, endoplasmic reticulum (ER)-, and chloroplast-localizations in tobacco leaf mesophyll cells. The results demonstrated that f-hEC-SOD was more efficiently expressed in the cytosolic fractions than in the ER or chloroplasts of tobacco cells. Our data further indicated that differently localized f-hEC-SOD and m-hEC-SOD displayed SOD enzyme activities, suggesting that the hEC-SODs expressed by plants may be functionally active. The f-hEC-SOD was expressed up to 3.8% of the total leaf soluble protein and the expression yield was calculated to be 313.7 μg f-hEC-SOD per g fresh weight of leaf. Overall, our results reveal that it was possible to express catalytically active hEC-SODs by means of a transient plant expression system in tobacco leaf cells.
['Park|Ki Youl|KY|', 'Kim|Eun Yu|EY|', 'Lee|Weontae|W|', 'Kim|Tae-Yoon|TY|', 'Kim|Woo Taek|WT|']
D002478:Cells, Cultured D003062:Codon D004926:Escherichia coli D015870:Gene Expression D006801:Humans D007700:Kinetics D018515:Plant Leaves D030821:Plants, Genetically Modified D011994:Recombinant Proteins D013482:Superoxide Dismutase D014026:Tobacco
Subcellular localization Tobacco (Nicotiana benthamiana L.) Human extracellular superoxide dismutase Plant-based protein expression Recombinant proteins