Detection of Gram-negative bacterial outer membrane vesicles using DNA aptamers

Area of Science:

• Biotechnology
• Molecular Biology
• Microbiology

Background:

• Pathogenic bacterial infections pose significant health risks.
• Current diagnostic tools struggle with accurate Gram-negative bacteria detection.

Purpose of the Study:

• To develop novel aptamers for detecting Gram-negative bacteria.
• To create an aptamer-based tool for identifying bacterial secretory cargo.

Main Methods:

• Systemic evolution of ligands by exponential enrichment (SELEX) was used to isolate aptamers.
• Toggle-cell-SELEX was employed against multiple Gram-negative bacterial species.
• An Enzyme-linked aptamer assay (ELAA) was constructed using selected aptamers.

Main Results:

• Two aptamers, GN6 and GN12, demonstrated selective binding to Gram-negative bacteria.
• The GN6 aptamer was used to create an ELAA for detecting bacterial outer membrane vesicles (OMVs).
• The GN6-ELAA detected as low as 25 ng/mL of bacterial OMVs with high sensitivity.

Conclusions:

• Developed aptamers show potential for improved Gram-negative bacteria detection.
• The aptamer-based tool can detect OMVs from multiple Gram-negative species.
• This technology could aid in medical diagnostics and early bioterrorism detection.