Construction of the genetic switches in response to mannitol based on artificial MtlR box

Abstract Synthetic biology has rapidly advanced from the setup of native genetic devices to design artificial elements able provide organisms with highly controllable functions. In particular, switches are crucial for deploying new layers regulation into engineered organisms. While assembly and mutagenesis have been extensively studied, limited progress made in rational due a lack understanding molecular mechanism by which specific transcription factor interacts its target gene. Here, reliable workflow is presented designing two categories elements, one switch element-MtlR box other transcriptional regulatory element- catabolite control protein A (CcpA) box. The MtlR was designed ON/OFF-state selection controlled mannitol. box-based structures can flexibly tuned both ON OFF states different output switchability response varied kind effectors. Different types CcpA boxes more markedly inducer sensitivities. Ultimately, OFF-state value reduced 90.69%, maximum change range presence 15.31-fold. This study presents switch, plug-and-play manner, great potential controlling flow metabolic pathway synthetic biology. Graphical