Neurosecretory protein GL (NPGL), recently identified from the chicken hypothalamus, is a hydrophobic peptide of 80 amino acid residues in length containing an intramolecular disulfide bond and amidated C-terminus. In this study, the research group optimized the synthesis of the entire 80 amino acid peptide sequence of rat NPGL using microwave-assisted solid-phase peptide synthesis and ChemMatrix® resin.
The structure of rat neurosecretory protein GL (NPGL).
The highest yields of NPGL were obtained when amino acid couplings were performed using HATU at 50 °C for 5 min and Fmoc deprotections were performed using 40% piperidine containing 0.1M HOBt. The intramolecular disulfide bond of NPGL was formed with the use of glutathione-containing redox buffer and 50% acetonitrile The synthesis, disulfide bond formation and purification afforded 10 mg of the final NPGL product.
The protocol for NPGL synthesis established in this study will contribute to the advancement of further functional analysis of NPGL and the production of similar long hydrophobic peptides in the future.
Microwave-assisted Fmoc-SPPS was performed on a Biotage® Syro Wave™ using Rink Amide ChemMatrix® resin.