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Updated: Jan 24, 2026

Reliably Engineering and Controlling Stable Optogenetic Gene Circuits in Mammalian Cells

Reliably Engineering and Controlling Stable Optogenetic Gene Circuits in Mammalian Cells

Published on: July 6, 2021

色素ベースの全細胞リードバイオセンサーの系統的評価：遺伝子回路工学における課題とバックグラウンドノイズ制御の重要な考慮事項

Yan Guo¹, Li-Dan Deng¹, Wen-Wu Gong¹

¹Shenzhen Prevention and Treatment Center for Occupational Diseases, Shenzhen, China.

Frontiers in bioengineering and biotechnology

|January 23, 2026

要旨

Introduction:

Despite advances in whole-cell biosensors for Pb(II) detection, background leakage and limited dynamic range hinder field deployment. This study systematically evaluates four diverse pbr operons and optimizes genetic circuit architectures to develop high-performance pigment-based Pb(II) biosensors.

Methods:

pbr operons from Cupriavidus metallidurans, Pseudomonas aeruginosa, and Klebsiella pneumoniae were engineered into E. coli TOP10 using decoupled violacein reporter circuits. Five optimization strategies were tested: transcriptional terminators, graded regulator expression (P₃₀₂-P_J23119 promoters), dual-gene copies, hybrid MerR-PbrR regulators, and circuit architecture variants. All assays used triplicate replicates (n = 3) across 8 time points and 12-15 Pb(II) concentrations.

Results:

The pLVPK-derived pKp-DV construct (PbrR.Kp) achieved optimal performance: LOD of 0.0008 μM, dynamic range 0.0061-50 μM, and high Pb(II) specificity. Transcription terminator insertion further reduced LOD to 0.0002 μM and background noise by 60%. However, regulator dosage and hybrid circuits showed minimal improvement, indicating limited synergistic benefits.

Discussion:

PbrR.Kp selection and transcriptional insulation are key strategies for reducing leakage. Hybrid circuits require more sophisticated designs. Future work should focus on chromosomal integration and environmental matrix validation to ensure the development of robust, field-ready sensors.

キーワード:

バックグラウンドノイズ制御遺伝子回路工学鉛(II)検出色素シグナル全細胞バイオセンサー

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