Bioluminescent Protein-Inhibitor Pair in the Design of a Molecular Aptamer Beacon Biosensing System

Anal Chem. 2020 Jun 2;92(11):7393-7398. doi: 10.1021/acs.analchem.0c00518. Epub 2020 May 21.


Although bioluminescent molecular beacons designed around resonance quenchers have shown higher signal-to-noise ratios and increased sensitivity compared with fluorescent beacon systems, bioluminescence quenching is still comparatively inefficient. A more elegant solution to inefficient quenching can be realized by designing a competitive inhibitor that is structurally very similar to the native substrate, resulting in essentially complete substrate exclusion. In this work, we designed a conjugated anti-interferon-γ (IFN-γ) molecular aptamer beacon (MAB) attached to a bioluminescent protein, Gaussia luciferase (GLuc), and an inhibitor molecule with a similar structure to the native substrate coelenterazine. To prove that a MAB can be more sensitive and have a better signal-to-noise ratio, a bioluminescence-based assay was developed against IFN-γ and provided an optimized, physiologically relevant detection limit of 1.0 nM. We believe that this inhibitor approach may provide a simple alternative strategy to standard resonance quenching in the development of high-performance molecular beacon-based biosensing systems.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Aptamers, Nucleotide / chemical synthesis
  • Aptamers, Nucleotide / chemistry*
  • Biosensing Techniques*
  • Copepoda / enzymology
  • Enzyme Inhibitors / chemistry*
  • Enzyme Inhibitors / pharmacology
  • Imidazoles / chemistry*
  • Imidazoles / pharmacology
  • Luciferases / antagonists & inhibitors
  • Luciferases / chemistry*
  • Luciferases / metabolism
  • Luminescent Measurements
  • Luminescent Proteins / antagonists & inhibitors
  • Luminescent Proteins / chemistry*
  • Luminescent Proteins / metabolism
  • Models, Molecular
  • Molecular Structure
  • Pyrazines / chemistry*
  • Pyrazines / pharmacology
  • Signal-To-Noise Ratio


  • Aptamers, Nucleotide
  • Enzyme Inhibitors
  • Imidazoles
  • Luminescent Proteins
  • Pyrazines
  • coelenterazine
  • Luciferases