Fig. 5: Effect of KS-AT linker junction positions on solubility and product formation.
From: Biosensor Guided Polyketide Synthases Engineering for Optimization of Domain Exchange Boundaries
a Testing synergy between KS-AT and post-AT linker junctions. The solubility coefficient was measured using the ΔarsB::Pibp GFP strain harboring DEBSM6 mCherry engineered with EpoM4 AT with different junction combinations. The color of the lines indicates the position of the post-AT junction, while the x-axis labels indicate the position of the KS-AT junction. b KS-AT junction effect on solubility coefficient measured using ΔarsB::Pibp GFP strain harboring DEBSM6 mCherry engineered with EpoM4 AT or TiaM4 AT with downstream junction at ds25. Sample pairs tested for in vitro production in (e) and (f) are marked with an arrow. Data points from neighboring junction positions that give identical polypeptide sequence due to homology between the parental PKS sequence and exchanged AT sequences are repeated. For reference, the DEBSM6 mCherry solubility coefficient was 71.1 ± 0.5, and its expression was induced with 250 µM IPTG. c, d Solubility data from (b) visualized on predicted protein structure of DEBSM6 engineered with EpoM4 AT (c) or TiaM4 AT (d). e, f In vitro production of desmethyl TKL (e) and methyl TKL (f) of variant pairs of DEBSM6 with EpoM4 AT. Reactions were sampled at 1 hour (red bars) and 24 hours (green bars). Data is presented as mean values of three biological replicates, dots are individual data points. Arb. units = arbitrary units. Source data are provided as a Source Data file.
