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Automated Modular High Throughput Exopolysaccharide Screening Platform Coupled with Highly Sensitive Carbohydrate Fingerprint Analysis
Published on: April 11, 2016
Development of a high-throughput screening method for exopolysaccharide-producing Streptococcus thermophilus based on
Zhiqiang Xiong1, Xin Tian1, Guangqiang Wang1
1Shanghai Engineering Research Center of Food Microbiology, School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China.
A new high-throughput screening (HTS) method using Congo red agar and microplate colorimetry was developed for exopolysaccharide (EPS) production in *S. thermophilus*. This efficient approach rapidly identifies high EPS-producing bacterial strains for industrial applications.
Area of Science:
- Food Science and Technology
- Microbiology
- Biotechnology
Background:
- Exopolysaccharides (EPS) are crucial for enhancing food texture as thickening or stabilizing agents.
- Conventional methods for analyzing and screening EPS are inefficient and time-consuming, hindering industrial production.
- A rapid and effective method is needed to accelerate the selection of high EPS-producing bacterial strains.
Purpose of the Study:
- To establish a high-throughput screening (HTS) program for exopolysaccharide (EPS) production in *S. thermophilus*.
- To develop a rapid qualitative and quantitative method for selecting high EPS-producing strains.
- To validate the efficiency and simplicity of the developed HTS method.
Main Methods:
- A two-step HTS program combining the Congo red agar (CRA) method for primary screening and a microplate colorimetric assay (MPC) for secondary screening.
- Construction of a mutant library of *S. thermophilus* using ribosome engineering.
- Validation of the HTS method by comparing results with the phenol-sulfuric acid assay (a classical EPS quantification method).
Main Results:
- The developed HTS method showed high correlation coefficients with the phenol-sulfuric acid assay (R² = 0.779 for CRA, R² = 0.862 for MPC), indicating its feasibility.
- Rapid identification of EPS-producing mutants with titers ranging from 50 mg/L to 200 mg/L from a library of over 300 colonies.
- The HTS method demonstrated simplicity and efficiency in isolating EPS-producing *S. thermophilus*.
Conclusions:
- A novel and efficient HTS method for screening exopolysaccharide (EPS) production in *S. thermophilus* has been successfully developed.
- This method serves as a valuable tool for rapid detection of EPS production capabilities and screening of genetically engineered strains.
- The HTS approach accelerates the selection of superior bacterial strains for enhanced food texture applications.
