Screening of a synthetic peptide library against glycosomal phosphoglycerate kinase of Trypanosoma brucei

Summary A synthetic peptide library composed of polystyrene beads was prepared employing the split-synthesis approach, using the 20 natural l-amino acids except for cysteine. This library was screened for interaction with glycosomal phosphoglycerate kinase (gPGK) of T. brucei, labelled with fluorescein or with biotin. Affinity beads were individually subjected to Edman microsequence analysis. The corresponding peptide sequences were synthesized as free peptide acids and evaluated for enzyme activity inhibition. The pentapeptide NWMMF was able to selectively inhibit gPGK with an IC₅₀ of 80 M.