The copper(II) binding tripeptide GHK, a valuable crystallization and phasing tag for macromolecular crystallography GHK Cu as a multifunctional copper peptide: synthesis routes, process engineering and emerging applications Systems Microbiology and Biomanufacturing Springer Nature Link GHK Cu Copper Tripeptide 1 Research Reagent 89030 95 5 GHK Cu Gly His Lys Cu Copper Tripeptide 1; Prezatide copper