Difference between revisions of "Part:BBa K4583013"

Revision as of 17:45, 11 October 2023

PesaS-RBS(B0034)-GFP(LVA)

PesaS is a natural EsaR-activated promoter.

Usage and Biology

QS system

Quorum sensing (QS) is a natural form of cell-cell communication that regulates the metabolic behaviour of bacteria based on changes in their local cell density. As cell density increases, signalling molecules accumulate and are sensed by QS-controlled gene expression regulators, which turn on relevant gene expression.

Esa I/R system

The Esa I/R system is quite special from traditional QS system. The EsaI/R QS system is homologous to the LuxI/R QS system and originates the maize pathogen--Pantoea stewartii subsp. stewartia. EsaR can act as both transcriptional activator and repressor. PesaR is a natural EsaR-repressed promoter, whereas PesaS is a natural EsaR-activated promoter. At low cell density (low ρ), EsaR binds to its esa box to turn off PesaR and turn on PesaS. In the presence of AHL, EsaR can bind to AHL and release from the DNA. Thus, at high cell density(high ρ), the PesaR is turned on and the PesaS is turned off[2].

Results

We characterized PesaS-RBS-GFP together with PesaRwt-RBS-mkate, PesaRc-RBS-mkate and PesaRp-RBS-mkate. The green curve in the figure shows the results for PesaS. PesaS expression peaks at around 4-6 h and then rapidly declines to 0 at around 8-10 h.

Reference

[1] Shong, J., & Collins, C. H. (2013). Engineering the esaR promoter for tunable quorum sensing- dependent gene expression. ACS synthetic biology, 2(10), 568–575. https://doi.org/10.1021/sb4000433

[2] Gu, F., Jiang, W., Mu, Y., Huang, H., Su, T., Luo, Y., Liang, Q., & Qi, Q. (2020). Quorum Sensing-Based Dual-Function Switch and Its Application in Solving Two Key Metabolic Engineering Problems. ACS synthetic biology, 9(2), 209–217. https://doi.org/10.1021/acssynbio.9b00290

Sequence and Features