Artificial Riboswitch Selection: A FACS-Based Approach

  • Zohaib Ghazi
  • Casey C. Fowler
  • Yingfu Li
Part of the Methods in Molecular Biology book series (MIMB, volume 1111)


Riboswitches have a number of characteristics that make them ideal regulatory elements for a wide range of synthetic biology applications. To maximize their utility, methods are required to create custom riboswitches de novo or to modify existing riboswitches to suit specific experimental needs. This chapter describes such a method, which exploits fluorescence-activated cell sorting (FACS) to quickly and efficiently sort through large libraries of riboswitch-like sequences to identify those with the desired activity. Suggestions for the experimental setup are provided, along with detailed protocols for testing and optimizing FACS conditions FACS selection steps, and follow-up assays to identify and characterize individual riboswitches.

Key words

Artificial riboswitch Aptamer Biosensor Fluorescence-activated cell sorting (FACS) High-throughput Enrichment 


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Zohaib Ghazi
    • 1
    • 2
    • 3
  • Casey C. Fowler
    • 1
    • 2
    • 3
  • Yingfu Li
    • 1
    • 2
    • 3
  1. 1.Department of Biochemistry and Biomedical SciencesMcMaster UniversityHamiltonCanada
  2. 2.Department of Chemistry and Chemical BiologyMcMaster UniversityHamiltonCanada
  3. 3.Michael G. DeGroote Institute for Infectious Disease ResearchMcMaster UniversityHamiltonCanada

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