Modification of response behavior of zinc sensing HydHG two-component system using a self-activation loop and genomic integration

• Published in: Bioprocess and biosystems engineering 2013-09, Vol.36 (9), p.1185-1190
• Main Authors: Pham, Van Dung, Ravikumar, Sambandam, Lee, Seung Hwan, Hong, Soon Ho, Yoo, Ik-Keun
• Format: Article
• Language: English
• Subjects: Biosensing Techniques - methods; Biosensors; Biosynthesis; Biotechnology; Chemistry; Chemistry and Materials Science; E coli; Environmental Engineering/Biotechnology; Escherichia coli; Escherichia coli - genetics; Escherichia coli - metabolism; Escherichia coli Proteins - biosynthesis; Escherichia coli Proteins - genetics; Escherichia coli Proteins - metabolism; Food Science; Genome, Bacterial; Industrial and Production Engineering; Industrial Chemistry/Chemical Engineering; Original Paper; Promoter Regions, Genetic; Signal transduction; Trans-Activators - biosynthesis; Trans-Activators - genetics; Zinc
• ISSN: 1615-7591; 1615-7605
• DOI: 10.1007/s00449-012-0845-7

Characterizing the dynamics of HydHG—a two-component transcriptional regulatory network for exogenous zinc in E. coli —is essential in understanding the biology of these regulatory and signaling pathways. Here, we used a synthetic biology strategy to modify the dynamic characteristics of the HydHG network in two ways. First, a self-activation loop for HydHG network was created under the control of zraP promoter, after which the threshold Zn 2+ concentration for the self-activated HydHG network significantly decreased from 200 to 10 μM. Second, the self-activation loop was integrated into the E. coli genome allowing the threshold Zn 2+ concentration to be elevated to 500 μM. As the threshold Zn 2+ concentration could be modified in both directions, the introduction of a self-activation loop and the entire genomic integration strategy may prove useful for the creation of a two-component bacterial biosensor with varying sensitivities.