NOT Gate Genetic Circuits to Control Gene Expression in Cyanobacteria

ACS Synth Biol. 2017 Dec 15;6(12):2175-2182. doi: 10.1021/acssynbio.7b00203. Epub 2017 Aug 21.

Abstract

To downregulate gene expression in cyanobacteria, we constructed NOT gate genetic circuits using orthogonal promoters and their cognate repressors regulated translationally by synthetic riboswitches. Four NOT gates were tested and characterized in five cyanobacterial strains using fluorescent reporter-gene assays. In comparison to alternative systems used to downregulate gene expression in cyanobacteria, these NOT gates performed well, reducing YFP reporter expression by 4 to 50-fold. We further evaluated these NOT gates by controlling the expression of the ftsZ gene, which encodes a prokaryotic tubulin homologue that is required for cell division and is essential for Synechococcus elongatus PCC 7942. These NOT gates would facilitate cyanobacterial genetic engineering or the study of essential cellular processes.

Keywords: circuits; cyanobacteria; downregulation; genetic engineering; synthetic biology.

Publication types

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

MeSH terms

  • Bacterial Proteins* / biosynthesis
  • Bacterial Proteins* / genetics
  • Cell Division / genetics*
  • Cytoskeletal Proteins* / biosynthesis
  • Cytoskeletal Proteins* / genetics
  • Down-Regulation*
  • Gene Expression Regulation, Bacterial*
  • Genetic Engineering
  • Synechococcus* / genetics
  • Synechococcus* / metabolism

Substances

  • Bacterial Proteins
  • Cytoskeletal Proteins
  • FtsZ protein, Bacteria