Fig. 7.

In vitro reconstitution of kistamicin Oxy enzymes. a Schematic illustration of in vitro reaction: kistamicin peptides were synthesised on hydrazine resin and converted into their CoA thioesters that were then loaded into the PCP-X_kis didomain by the phosphopantetheinyl transferase Sfp. After incubation with OxyA_kis, OxyC_kis and/or OxyB_tei (different combinations), the peptide was cleaved from the PCP by the addition of methylamine and subsequently analysed by HPLC-MS. b Example shown for the peptide K4-7D: in the control reaction, only linear peptide is detected. Reactions containing OxyC_kis led to the formation of several monocyclic products and traces of bicyclic compounds. Structures of synthesised peptide probes and turnover results of c K4-7 (4-D) (left) and (4-L) (right), d K2-4 (4-D) (left) and (4-L) (right), e K3-6, f K3-7, g K1-6, h K1-4 and i K1-7. Detection of linear peptide mass is indicted in dark grey, of monocyclic compound in purple and bicyclic compound in blue. Source data are provided as a Source Data file