Fig. 2From: Self-regulated 1-butanol production in Escherichia coli based on the endogenous fermentative controlCloning of the endogenous FRE ldhA , FRE frd , FRE adhE , and FRE ackA to drive the genes for 1-butanol synthesis. a Coverage of the native FRE cloned (solid gray block) upstream of each fermentative gene (black arrow block) in E. coli, including the endogenous transcription factor-binding site, promoter, and ribosomal-binding site. The neighboring genes are denoted by hollow gray arrow blocks while the neighboring promoters are drawn with gray elbow arrow. b Expression of the 1-butanol pathway genes distributed among three plasmids by the cloned FRE. Operon atoB-adhE2-crt-hbd is harbored on plasmid with ColE1 origin, gene ter is carried on plasmid with Cola origin, and gene fdh is carried on plasmid with pSC101 origin. Each plasmid was paired with the four different FRE individually, creating a total of 12 plasmid constructs (pRW13–pRW24). TF, transcription factor; RBS, ribosomal-binding siteBack to article page