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09:03
Multiplex PCR Assay for Typing of Staphylococcal Cassette Chromosome Mec Types I to V in Methicillin-resistant Staphylococcus aureus
Published on: September 5, 2013
A DNA Spiegelmer to staphylococcal enterotoxin B
Werner G Purschke1, Falko Radtke, Frank Kleinjung
1NOXXON Pharma AG, Max-Dohrn-Strasse 8-10, 10589 Berlin, Germany.
Nucleic Acids Research
|June 12, 2003
Summary
Researchers developed Spiegelmers, mirror-image DNA ligands, to target bacterial staphylococcal enterotoxin B. This approach successfully generated high-affinity aptamers against a protein domain, showing potential for large protein targets.
Area of Science:
- Biochemistry
- Molecular Biology
- Oligonucleotide Therapeutics
Background:
- Staphylococcal enterotoxin B (SEB) is implicated in severe diseases.
- SEB is a 28 kDa protein with 239 amino acids.
- Full-length SEB is challenging for chemical peptide synthesis.
Purpose of the Study:
- To generate biologically stable mirror-image oligonucleotide ligands (Spiegelmers) against SEB.
- To assess the feasibility of targeting large protein toxins using a domain-based approach.
- To develop high-affinity aptamers for SEB detection or neutralization.
Main Methods:
- In vitro selection experiments using DNA against a mirror-image D-peptide domain of SEB.
- Synthesis and characterization of enantiomeric L-DNA Spiegelmers.
- Affinity measurements using dissociation constants (Kd) for peptide-oligonucleotide and Spiegelmer-protein interactions.
Main Results:
- High-affinity D-DNA aptamers were generated against the SEB D-peptide domain.
- Enantiomeric L-DNA Spiegelmers exhibited comparable binding to the L-peptide domain.
- Spiegelmers demonstrated effective binding to the full-length SEB protein with a Kd of approximately 420 nM.
Conclusions:
- Spiegelmers can be successfully generated against large protein targets by focusing on stable domains.
- The domain-based approach is a viable strategy for developing aptamers against complex protein toxins.
- This study validates Spiegelmers as potential therapeutic or diagnostic agents for SEB-related conditions.
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