The molecular interaction of six single-stranded DNA aptamers to cardiac troponin I revealed by docking and molecular dynamics simulation

PLoS One. 2024 May 15;19(5):e0302475. doi: 10.1371/journal.pone.0302475. eCollection 2024.

Abstract

Cardiac troponin I (cTnI) is a cardiac biomarker for diagnosing ischemic heart disease and acute myocardial infarction. Current biochemical assays use antibodies (Abs) due to their high specificity and sensitivity. However, there are some limitations, such as the high-cost production of Abs due to complex instruments, reagents, and steps; the variability of Abs quality from batch to batch; the low stability at high temperatures; and the difficulty of chemical modification. Aptamer overcomes the limitations of antibodies, such as relatively lower cost, high reproducibility, high stability, and ease of being chemically modified. Aptamers are three-dimensional architectures of single-stranded RNA or DNA that bind to targets such as proteins. Six aptamers (Tro1-Tro6) with higher binding affinity than an antibody have been identified, but the molecular interaction has not been studied. In this study, six DNA aptamers were modeled and docked to cTnI protein. Molecular docking revealed that the interaction between all aptamer and cTnI happened in the similar cTnI region. The interaction between aptamer and cTnI involved hydrophobic interaction, hydrogen bonds, π-cation interactions, π-stack interactions, and salt-bridge formation. The calculated binding energy of all complexes was negative, which means that the complex formation was thermodynamically favorable. The electrostatic energy term was the main driving force of the interaction between all aptamer and cTnI. This study could be used to predict the behavior of further modified aptamer to improve aptamer performance.

MeSH terms

  • Aptamers, Nucleotide* / chemistry
  • Aptamers, Nucleotide* / metabolism
  • DNA, Single-Stranded* / chemistry
  • DNA, Single-Stranded* / metabolism
  • Humans
  • Hydrogen Bonding
  • Molecular Docking Simulation*
  • Molecular Dynamics Simulation*
  • Protein Binding
  • Thermodynamics
  • Troponin I* / chemistry
  • Troponin I* / metabolism

Grants and funding

The authors received research grants from the The Ministry of Education, Culture, Research, 269 and Technology of the Republic of Indonesia through a research scheme of Program 270 Penelitian Kolaborasi Indonesia (PPKI) 2021 hosted by Universitas Sumatera Utara and the research fund from Institut Teknologi Bandung through Riset Unggulan Pusat and Pusat Penelitian (RU3P) 2024 program under Lembaga Pengembangan Ilmu dan Teknologi (LPIT) with the grant ID: 766.15/IT1.B07.5/TA.00/2024. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.