DNA aptamers selection for Staphylococcus aureus cells by SELEX and Cell-SELEX

Mol Biol Rep. 2023 Jan;50(1):157-165. doi: 10.1007/s11033-022-07991-0. Epub 2022 Oct 31.

Abstract

Background: Staphylococcus aureus is the most common bacteria found in skin, soft tissues, bone, and bone prostheses infections. The aim of this study was to select DNA aptamers for S. aureus to be applied in the diagnosis of bacteria.

Methods and results: We used SELEX (Systematic Evolution of Ligands by EXponencial Enrichment) for peptidoglycan followed by cell-SELEX with S. aureus cells as target. Four sequences showed significantly higher binding to S. aureus distinguishing it from the control cells of other significant microbial species: Escherichia coli, Candida albicans, Streptococcus pyogenes and Streptococcus pneumoniae. In particular, ApSA1 (Kd = 62.7 ± 5.6 nM) and ApSA3 (Kd = 43.3 ± 3.0 nM) sequences combined high affinity and specificity for S. aureus, considering all microorganisms tested.

Conclusions: Our results demonstrated that these aptamers were able to identify peptidoglycan in the S. aureus surface and have great potential for use in the development of radiopharmaceuticals capable to identify S. aureus infectious foci, as well as in other aptamer-based methodologies for bacteria diagnosis.

Keywords: Aptamers; Bacterial infections; Diagnosis; Peptidoglycan; Staphylococcus aureus.

MeSH terms

  • Aptamers, Nucleotide* / chemistry
  • Aptamers, Nucleotide* / genetics
  • Escherichia coli / metabolism
  • Humans
  • Peptidoglycan
  • SELEX Aptamer Technique / methods
  • Staphylococcal Infections* / microbiology
  • Staphylococcus aureus / genetics
  • Staphylococcus aureus / metabolism

Substances

  • Aptamers, Nucleotide
  • Peptidoglycan