Fig. 8
From: Engineered bidirectional promoters enable rapid multi-gene co-expression optimization
The library of BDPs and BDTs facilitates the assembly and transcriptional fine-tuning of multi-gene pathways demonstrated with the four gene (crtE, crtB, crtI, crtY) model pathway of β-carotene biosynthesis. a Using BDPs and BDTs for pathway assembly reduces construct length and the number of parts required. Twelve bidirectional constructs were assembled by combining inducible or constitutive BDPs and combinations thereof (Induc.+const.) with a BDT and two MDTs. See Supplementary Fig. 5d for assembly strategy and supporting file Supplementary Data 2 (sheet “Carotenoid pathway constructs”) contains detailed information on the BDPs/BDTs used. For the BDPs, a coloring scheme similar to Fig. 5 was used. T* natural bidirectional terminator between the S. cerevisiae IDP1 and PEX19 genes, T+ natural bidirectional terminator between the P. pastoris TEF1 and GDM1 genes. The bidirectionalized PFLD1-366+HHT1-91 was used. b β-Carotene titers obtained with strains based on the bidirectional constructs shown in a span a 12-fold range matching or surpassing conventional PAOX1- and PGAP-based designs. Mean values and standard deviations of biological triplicate cultivations in shake flasks are shown (HPLC measurements)
