Evidence of metal binding activities of pentadecapeptide from Panax ginseng

A tetradecapeptide from ginseng (Panax ginseng) root showing anti-lipolytic activity in an isolated rat fat cell assay was chemically synthesized for analysis of metal binding activities in vitro. Binding activities against several metal ions were analysed by measuring mobility shifts during capillary zone electrophoresis experiments. The ginseng polypeptide (GPP) showed the greatest increase in effective molecular electrophoretic mobility in the presence of Mg2+. Mobility was also affected in the presence of La3+, Mn2+, Ca2+ and Zn2+ ions. Analysis with the dye Stains-all revealed GPP to possess a cation binding site similar to those in Ca(2+)-binding proteins. GPP thus appears to be a metal binding peptide. The results of this analysis suggested that GPP may perform its anti-lipolytic activities through an ability to modulate the level of free cellular Mg2+ and Mn2+ ions.