An examination of microcystin-LR accumulation and toxicity using tethered bilayer lipid membranes (tBLMs)

Jordan A. Facey, Joel R. Steele, Jake P. Violi, Simon M. Mitrovic, Charles Cranfield

Research output: Contribution to journalArticleResearchpeer-review

5 Citations (Scopus)

Abstract

Microcystin-LR (MC-LR) is a potent cyanobacterial toxin responsible for animal and human poisonings worldwide. MC-LR is found in organisms throughout the foodweb, however there is conjecture regarding whether it biomagnifies. Few studies have investigated how MC-LR interacts with lipid membranes, a determinant of biomagnification potential. We tested whether 1 μM MC-LR irreversibly associates with lipid bilayers or causes the creation of pore defects upon short and long-term exposure. Using tethered bilayer lipid membranes (tBLMs), we observed an increase in membrane conduction in tBLMs, representing an interaction of microcystin-LR with the lipid bilayer and a change in membrane packing properties. However, there were minimal changes in membrane capacitance upon short and long-term exposure, and MC-LR exhibited a rapid off-rate. Upon 24 h exposure to the toxin, no lipophilic multimeric complexes were detected capable of altering the toxin's off-rate. There was no evidence of the creation of new pores. This study demonstrates that MC-LR does not irreversibly imbed itself into lipids membranes after short or long-term exposure and suggests MC-LR does not biomagnify through the food web via lipid storage.

Original languageEnglish
Pages (from-to)51-56
Number of pages6
JournalToxicon
Volume158
DOIs
Publication statusPublished - Feb 2019
Externally publishedYes

Keywords

  • Biomagnification
  • Cyanobacteria
  • Microcystin-LR
  • Tethered bilayer lipid membrane

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