Single-stranded DNA (ssDNA) Aptamer targeting SipA protein inhibits Salmonella Enteritidis invasion of intestinal epithelial cells

Int J Biol Macromol. 2020 Apr 1:148:518-524. doi: 10.1016/j.ijbiomac.2020.01.132. Epub 2020 Jan 15.

Abstract

Salmonella Enteritidis is an important pathogen that can invade the intestinal cells of its host causing salmonellosis. SipA protein, an effector protein secreted by T3SS, maintains invasion of host cells more efficient. Thus, inhibitory aptamers against SipA protein were developed using magnetic bead-based Systematic Evolution of Ligands by Exponential Enrichment (SELEX) method. The enriched sequences were obtained after 9 SELEX rounds. Among which, an aptamer namely Apt17 displayed Kd values equivalent to 114.9 and 63.4 nM at 27 °C and 37 °C, respectively. The effect of Apt17 on adhesion and invasion of Caco-2 cells by the tested strains was determined. While the adhesion and invasion of Salmonella Enteritidis TM 6 were inhibited by 70% and 37.7%, those of Salmonella Enteritidis TM 68 were inhibited by 45.71% and 39.5% respectively. These results represent a corner stone for future studies that could aim to develop putative inhibitors against Salmonellosis.

Keywords: Aptamer; Salmonella invasion; Salmonella invasion protein A.

MeSH terms

  • Aptamers, Nucleotide*
  • Bacterial Adhesion
  • Bacterial Proteins / genetics*
  • Bacterial Proteins / metabolism
  • Base Sequence
  • Caco-2 Cells
  • DNA, Single-Stranded / chemistry*
  • Humans
  • Intestinal Mucosa / metabolism*
  • Intestinal Mucosa / microbiology*
  • Microfilament Proteins / genetics*
  • Microfilament Proteins / metabolism
  • Recombinant Proteins
  • SELEX Aptamer Technique / methods
  • Salmonella enteritidis / physiology*

Substances

  • Aptamers, Nucleotide
  • Bacterial Proteins
  • DNA, Single-Stranded
  • Microfilament Proteins
  • Recombinant Proteins
  • SipA protein, Salmonella