Fig. 1.

Enzymatic activity of recombinant VyPAL1–3 and VyAEP1. (A) Reaction scheme of ligase-mediated cyclization of GN14-SL. (B) Analytical HPLC and MALDI-TOF mass spectrometry data of VyPAL2-mediated cyclization under different reaction pH values. The asterisk indicates racemized synthetic GN14-SL. Note that MALDI-TOF MS was more sensitive against cyclic cGN14 than the linear species. (C) Quantitative summary of product ratio and reaction yield of each enzyme analyzed using RP-HPLC. For each reaction, a molar ratio of purified active enzyme:GN14-SL of 1:500 was mixed and reacted at 37 °C for 10 min. Average yield and SDs were calculated from experiments performed in triplicate.