Abstract: In an earlier study, we isolated potamin-1 (PT-1), a 5.6-kDa trypsin-chymotrypsin protease inhibitor, from the tubers of a potato strain (Solanum tuberosum L cv. Gogu Valley). We established that PT-1 strongly inhibits pathogenic microbial strains, but not human bacterial strains, and that its sequence shows 62% homology with a serine protease inhibitor. In the present study, we isolated an antifungal and antibacterial peptide with no cytotoxicity from tubers of the same potato strain. The peptide (peptide-G2, PG-2) was isolated using salt-extraction, ultrafiltration and reverse-phase high performance liquid chromatography (RP-HPLC). Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS) showed the protein to have a molecular mass of 3228.5 Da, while automated Edman degradation showed the N-terminal sequence of PG-2 to be LVKDNPLDISPKQVQALCTDLVIRCMCCC-. PG-2 exhibited antimicrobial activity against Candida albicans, a human pathogenic yeast strain, and Clavibacter michiganensis subsp. michiganensis, a plant late blight strain. PG-2 also showed antibacterial activity against Staphylococcus aureus, but did not lyse human red blood cells and was thermostable. Overall, these results suggest PG-2 may be a good candidate to serve as a natural antimicrobial agent, agricultural pesticide and/or food additive.
Keywords: peptide-G2; RP-HPLC; N-terminal sequence; human pathogenic; antimicrobial agent
Export to BibTeX
MDPI and ACS Style
Kim, J.-Y.; Gopal, R.; Kim, S.Y.; Seo, C.H.; Lee, H.B.; Cheong, H.; Park, Y. PG-2, a Potent AMP against Pathogenic Microbial Strains, from Potato (Solanum tuberosum L cv. Gogu Valley) Tubers Not Cytotoxic against Human Cells. Int. J. Mol. Sci. 2013, 14, 4349-4360.
Kim J-Y, Gopal R, Kim SY, Seo CH, Lee HB, Cheong H, Park Y. PG-2, a Potent AMP against Pathogenic Microbial Strains, from Potato (Solanum tuberosum L cv. Gogu Valley) Tubers Not Cytotoxic against Human Cells. International Journal of Molecular Sciences. 2013; 14(2):4349-4360.
Kim, Jin-Young; Gopal, Ramamourthy; Kim, Sang Y.; Seo, Chang H.; Lee, Hyang B.; Cheong, Hyeonsook; Park, Yoonkyung. 2013. "PG-2, a Potent AMP against Pathogenic Microbial Strains, from Potato (Solanum tuberosum L cv. Gogu Valley) Tubers Not Cytotoxic against Human Cells." Int. J. Mol. Sci. 14, no. 2: 4349-4360.