Genetic circuits to detect nanomaterial triggered toxicity through engineered heat shock response mechanism
Date
2019Source Title
ACS Synthetic Biology
Print ISSN
2161-5063
Publisher
American Chemical Society
Volume
8
Issue
10
Pages
2404 - 2417
Language
English
Type
ArticleItem Usage Stats
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Abstract
Biocompatibility assessment of nanomaterials has been of great interest due to their potential toxicity. However, conventional biocompatibility tests fall short of providing a fast toxicity report. We developed a whole cell based biosensor to track biocompatibility of nanomaterials with the aim of providing fast feedback to engineer them with lower toxicity levels. We engineered promoters of four heat shock response (HSR) proteins utilizing synthetic biology approaches. As an initial design, a reporter coding gene was cloned downstream of the selected promoter regions. Initial results indicated that native heat shock protein (HSP) promoter regions were not very promising to generate signals with low background signals. Introducing riboregulators to native promoters eliminated unwanted background signals almost entirely. Yet, this approach also led to a decrease in expected sensor signal upon stress treatment. Thus, a repression based genetic circuit, inspired by the HSR mechanism of Mycobacterium tuberculosis, was constructed. These genetic circuits could report the toxicity of quantum dot nanoparticles in 1 h. Our designed nanoparticle toxicity sensors can provide quick reports, which can lower the demand for additional experiments with more complex organisms.
Keywords
NanotoxicityNanomaterial triggered toxicity
Heat shock response
Synthetic biology
Whole-cell biosensors