Detection of bacterial 16S rRNA using a molecular beacon-based X sensor

Area of Science:

• Biochemistry
• Molecular Biology
• Nanotechnology

Background:

• Analyzing long, structurally complex RNA molecules like ribosomal RNA (rRNA) in solution presents significant challenges.
• Existing methods often require harsh conditions or lack specificity for precise RNA identification.

Purpose of the Study:

• To develop a sophisticated biosensor for analyzing long, structurally constrained RNA in homogeneous solution at ambient temperatures.
• To achieve high specificity and real-time detection of target RNA sequences.

Main Methods:

• A three-component biosensor was designed, comprising a molecular beacon probe and two DNA adaptor strands.
• One adaptor strand unwinds RNA secondary structures, while the second ensures specific hybridization to the target RNA.
• The sensor and target RNA form a four-stranded DNA crossover (X) structure.

Main Results:

• The biosensor successfully detected Escherichia coli 16S rRNA in real time with a detection limit of approximately 0.17 nM.
• High specificity was demonstrated by differentiating between E. coli and Bacillus subtilis 16S rRNA sequences.
• The sensor exhibited rapid response times, detecting the analyte within seconds.

Conclusions:

• This sophisticated biosensor offers a highly specific and sensitive method for analyzing long RNA molecules in homogeneous solution.
• The developed system provides rapid, real-time detection and differentiation of bacterial 16S rRNA, with potential applications in diagnostics and research.