Biosensor-enabled droplet microfluidic system for the rapid screening of 3-dehydroshikimic acid produced in Escherichia
- PDF / 1,052,116 Bytes
- 6 Pages / 595.276 x 790.866 pts Page_size
- 1 Downloads / 191 Views
BIOTECHNOLOGY METHODS - SHORT COMMUNICATION
Biosensor‑enabled droplet microfluidic system for the rapid screening of 3‑dehydroshikimic acid produced in Escherichia coli Ran Tu1,2 · Liangpo Li1 · Huiling Yuan1 · Ronglin He1,3 · Qinhong Wang1,2 Received: 15 June 2020 / Accepted: 21 September 2020 © Society for Industrial Microbiology and Biotechnology 2020
Abstract Genetically encoded biosensors are powerful tools used to screen metabolite-producing microbial strains. Traditionally, biosensor-based screening approaches also use fluorescence-activated cell sorting (FACS). However, these approaches are limited by the measurement of intracellular fluorescence signals in single cells, rather than the signals associated with populations comprising multiple cells. This characteristic reduces the accuracy of screening because of the variability in signal levels among individual cells. To overcome this limitation, we introduced an approach that combined biosensors with droplet microfluidics (i.e., fluorescence-activated droplet sorting, FADS) to detect labeled cells at a multi-copy level and in an independent droplet microenvironment. We used our previously reported genetically encoded biosensor, 3-dehydroshikimic acid (3-DHS), as a model with which to establish the biosensor-based FADS screening method. We then characterized and compared the effects of the sorting method on the biosensor-based screening system by subjecting the same mutant library to FACS and FADS. Notably, our developed biosensor-enabled, droplet microfluidics-based FADS screening system yielded an improved positive mutant enrichment rate and increased productivity by the best mutant, compared with the single-cell FACS system. In conclusion, the combination of a biosensor and droplet microfluidics yielded a more efficient screening method that could be applied to the biosensor-based high-throughput screening of other metabolites. Keywords Droplet microfluidics · High-throughput screening · Metabolite · Fluorescence signal · Strain engineering
Introduction In recent years, major advances in metabolic engineering and synthetic biology have led to the construction of increasingly efficient microbial cell factories for the production of high value-added metabolites, such as amino acids, proteins, organic acids and aromatic compounds [22]. However, many of these microbial cell factories could not meet the * Ronglin He [email protected] * Qinhong Wang [email protected] 1
Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
2
Key Laboratory of Systems Microbial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
3
Tianjin Key Laboratory of Industrial Biology Systems and Processing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
commercial requirements for the synthesis of these metabolites, thus necessitating strain engineering or evolution to improve the production capacity. Therefore, the development of selection strateg
Data Loading...
