Fig. 5
Application of a self-induced dynamic temporal regulation cascade circuit. a Diagram of the CRISPRi system combined with a self-induced dynamic temporal regulation cascade circuit for PHB production (PHB production followed by inhibition of the TCA cycle is introduced as an example. During the growth of E. coli, 3OC12HSL secreted by LasI synthase binds to TraR after reaching a certain concentration threshold, and the complex formed activates Ptra*, which in turn activates phbcab. At the same time, Ptra* also activates LasR, and the complex formed upon binding to 3OC12HSL potentiates the activation of Plas, which then activates the transcription of dCas9 and sgRNA. The bound complex targets and represses the expression of gltA in the genome, which in turn represses the TCA cycle and promotes the flux of more acetyl-CoA into the PHB production pathway). b PHB content of fermentation strains