Abstract:

Fmoc solidphase peptide synthesis was used to synthesize cyclic peptide in light of the known isocitrate lyase linear peptide sequence according to the end to end way. Mass spectrometry demonstrates that the measured value of relative molecular mass is consistent with the theoretical value. Inhibition test confirms that the cyclic peptide shows significant inhibition to the ICL activity (the inhibition rate was more than 50%). At the same time, halflife of linear peptide and that of cyclic peptide in plasma were measured by HPLC. Results indicate that halflife of cyclic peptide in plasma amounts to 11 min, which is increased by 175% compared with that of linear peptide.

Key words: isocitrate lyase, peptide, inhibitor, cyclic peptide