Engineered systems of inducible anti-repressors for the next generation of biological programming

Nat Commun. 2020 Sep 7;11(1):4440. doi: 10.1038/s41467-020-18302-1.

Abstract

Traditionally engineered genetic circuits have almost exclusively used naturally occurring transcriptional repressors. Recently, non-natural transcription factors (repressors) have been engineered and employed in synthetic biology with great success. However, transcriptional anti-repressors have largely been absent with regard to the regulation of genes in engineered genetic circuits. Here, we present a workflow for engineering systems of non-natural anti-repressors. In this study, we create 41 inducible anti-repressors. This collection of transcription factors respond to two distinct ligands, fructose (anti-FruR) or D-ribose (anti-RbsR); and were complemented by 14 additional engineered anti-repressors that respond to the ligand isopropyl β-d-1-thiogalactopyranoside (anti-LacI). In turn, we use this collection of anti-repressors and complementary genetic architectures to confer logical control over gene expression. Here, we achieved all NOT oriented logical controls (i.e., NOT, NOR, NAND, and XNOR). The engineered transcription factors and corresponding series, parallel, and series-parallel genetic architectures represent a nascent anti-repressor based transcriptional programming structure.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Bioengineering / methods*
  • Escherichia coli Proteins / metabolism
  • Gene Expression / physiology
  • Gene Regulatory Networks
  • Lac Repressors / antagonists & inhibitors*
  • Lac Repressors / chemical synthesis
  • Ligands
  • Repressor Proteins / antagonists & inhibitors
  • Repressor Proteins / chemical synthesis
  • Synthetic Biology / methods
  • Transcription Factors / chemical synthesis
  • Transcription Factors / metabolism

Substances

  • Escherichia coli Proteins
  • Lac Repressors
  • Ligands
  • Repressor Proteins
  • Transcription Factors