Objectives: To establish an efficient expression system for a fusion protein GST-pgLTP (Lipid Transfer Protein) and to test its antifungal activity.
Results: The nucleotide sequence of LTP gene was obtained from Panax ginseng using RT-PCR. The ORF of the cDNA is 363 bp, codING for a protein OF 120 amino acids with a calculated MW of 12.09 kDa. The pgLTP gene with a His6-tag at the C-terminus was cloned into the pGEX-6p1 vector to generate a GST-fusion pgLTP protein construct that was expressed in Escherichia coli Rosetta. Following purification by Ni-NTA, the fusion protein exhibited antifungal activity against five fungi found in ginseng.
Conclusion: The fusion protein GST-pgLTP has activity against a broad spectrum of phytopathogenic fungi, and can potentially be adapted for production to combat fungal diseases that affect P. ginseng.
Keywords: Antifungal activity; Lipid transfer proteins; Panax ginseng; Protein expression and purification.