Biasing effects of receptor-ligand complexes on protein-unfolding statistics

Phys Rev E. 2016 Oct;94(4-1):042412. doi: 10.1103/PhysRevE.94.042412. Epub 2016 Oct 13.

Abstract

Protein receptor-ligand pairs are increasingly used as specific molecular handles in single-molecule protein-unfolding experiments. Further, known marker domains, also referred to as fingerprints, provide unique unfolding signatures to identify specific single-molecule interactions, when receptor-ligand pairs themselves are investigated. We show here that in cases where there is an overlap between the probability distribution associated with fingerprint domain unfolding and that associated with receptor-ligand dissociation, the experimentally measured force distributions are mutually biased. This biasing effect masks the true parameters of the underlying free energy landscape. To address this, we present a model-free theoretical framework that corrects for the biasing effect caused by such overlapping distributions.

MeSH terms

  • Ligands
  • Models, Statistical
  • Protein Folding
  • Protein Unfolding*
  • Proteins / chemistry*

Substances

  • Ligands
  • Proteins