Synthesis of Heavily Glycosylated PeptideαThioester

Synthesis of full length and truncated microcin B17 analogues as DNA gyrase poisons

Using a combination of solid-phase peptide synthesis and fragment assembly strategies a library of full-length and truncated analogues of the antibacterial post-translationally modified peptide microcin B17 have been synthesised. Both antibacterial and DNA gyrase poisoning activities are also described for the synthetic analogues.

Native N-glycopeptide thioester synthesis through N→S acyl transfer

Peptide thioesters are important tools for the total synthesis of proteins using native chemical ligation (NCL). Preparation of glycopeptide thioesters, that enable the assembly of homogeneously glycosylated proteins, is complicated by the perceived fragile nature of the sugar moiety. Herein, we demonstrate the compatibility of thioester formation via N→S acyl transfer with native N-glycopeptides and report observations that will aid in their preparation.

Total synthesis of microcin B17 via a fragment condensation approach

The total synthesis of the 43 amino acid antibacterial peptide Microcin B17 (MccB17) is described. The natural product was synthesized via a convergent approach from a heterocycle-derived peptide and peptide thioester fragments prepared via Fmoc-strategy solid phase peptide synthesis (SPPS). Final assembly was achieved in an efficient manner using two Ag(I)-assisted peptide ligation reactions to afford MccB17 in excellent overall yield.