Cell SELEX-based DNA aptamer selection targeting Streptococcus agalactiae using high-throughput sequencing: toward...

Area of Science:

• Aquatic Animal Health
• Microbiology
• Biotechnology

Background:

• Streptococcus agalactiae causes significant disease outbreaks in tilapia, leading to substantial economic losses in aquaculture.
• Effective diagnostic tools and therapeutic strategies are crucial for managing S. agalactiae infections in farmed fish.

Purpose of the Study:

• To isolate and characterize single-stranded DNA aptamers with specific binding affinity to S. agalactiae.
• To evaluate the potential of these aptamers for detecting S. agalactiae and as molecular probes in aquaculture applications.

Main Methods:

• A 10-round whole-cell Systemic Evolution of Ligands by Exponential Enrichment (SELEX) procedure was employed.
• High-throughput sequencing was used to analyze enriched DNA libraries, yielding over 126,000 unique aptamer sequences.
• Sequence frequency analysis identified candidate aptamers, including SA1 and SA2.

Main Results:

• The study successfully identified DNA aptamers with specific binding affinity to S. agalactiae.
• High-throughput sequencing revealed a large number of unique aptamer sequences from the SELEX process.
• The selected aptamers demonstrated potential for detecting S. agalactiae.

Conclusions:

• Combining whole-cell SELEX, high-throughput sequencing, and aptamer-structure analysis is a valid approach for studying aptamer-bacterial cell surface interactions.
• The identified aptamers hold promise for S. agalactiae detection, surface protein identification, host-pathogen interaction studies, and targeted drug delivery in aquaculture.