Fig. 1

DNA copy number optimization and site directed mutagenesis of CAS for increased canadine titer. a (S)-canadine titers for S. cerevisiae expressing the protoberberine biosynthetic pathway with varied TfCAS constructs (Table 1). Int, chromosomally integrated; HCP, high copy plasmid; LCP, low copy plasmid. LC–MS/MS analysis was performed on media supernatant collected after 96 h of cultivation in YNB-DO (2 % dextrose) with 2 mM rac-norlaudanosoline. Error bars represent mean values ±1 SD of at least three biological replicates. b Confocal fluorescence microscopy images of TfCAS-GFP and GFP control. Percentages indicate the percent of cells that were fluorescent out of at least 300 cells counted from three separate clonal cultures. Scale bars 5 μm