title: Effect of transition metals on recovery from plasma of the growth-modulating tripeptide glycylhistidyllysine.
abstract: Isolation and purification of growth-modulating peptides from biological sources is often accompanied by excessive losses of bioactive material. During the isolation of a growth-modulating tripeptide glycylhistidyllysine (GHL) from human plasma, copper and iron were found to co-isolate with the peptide. Studies with [3H]GHL demonstrated that these metals interfere at several steps of the procedure for the isolation of GHL from plasma (gel filtration chromatography, high-pressure silica-gel). Removal of these metals with an insoluble chelating resin (Cellex 100) enhanced recovery of [3H]GHL from plasma 8-fold. These results suggest that removal of transition metals may aid in the recovery of peptides which are difficult to isolate from biological sources.
mesh_terms: D002614:Chelating Agents; D002850:Chromatography, Gel; D003300:Copper; D004577:Electron Probe Microanalysis; D006133:Growth Substances / Q000097:blood*; D007501:Iron; D009842:Oligopeptides / Q000097:blood*
chemical_list: D002614:Chelating Agents; D006133:Growth Substances; D009842:Oligopeptides; C020905:glycyl-histidyl-lysine; D003300:Copper; D007501:Iron