Quantitative Estimation of Cyclotide-Induced Bilayer Membrane Disruption by Lipid Extraction with Mesoscopic Simulation

J Chem Inf Model. 2021 Jun 28;61(6):3027-3040. doi: 10.1021/acs.jcim.1c00332. Epub 2021 May 19.

Abstract

Cyclotide-induced membrane disruption is studied at the microsecond timescale by dissipative particle dynamics to quantitatively estimate a kinetic rate constant for membrane lipid extraction with a ″sandwich″ interaction model where two bilayer membranes enclose a cyclotide/water compartment. The obtained bioactivity trends for cyclotides Kalata B1, Cycloviolacin O2, and selected mutants with different membrane types are in agreement with experimental findings: For all membranes investigated, Cycloviolacin O2 shows a higher lipid extraction activity than Kalata B1. The presence of cholesterol leads to a decreased cyclotide activity compared to cholesterol-free membranes. Phosphoethanolamine-rich membranes exhibit an increased membrane disruption. A cyclotide's ″hydrophobic patch″ surface area is important for its bioactivity. A replacement of or with charged amino acid residues may lead to super-mutants with above-native activity but without simple charge-activity patterns. Cyclotide mixtures show linearly additive bioactivities without significant sub- or over-additive effects. The proposed method can be applied as a fast and easy-to-use tool for exploring structure-activity relationships of cyclotide/membrane systems: With the open software provided, the rate constant of a single cyclotide/membrane system can be determined in about 1 day by a scientific end-user without programming skills.

MeSH terms

  • Cyclotides*
  • Hydrophobic and Hydrophilic Interactions
  • Kinetics
  • Lipids
  • Structure-Activity Relationship

Substances

  • Cyclotides
  • Lipids