Dual effect of non-ionic detergent Triton X-100 on insulin amyloid formation

Katarina Siposova, Erik Sedlak, Tibor Kozar, Michal Nemergut, Andrey Musatov

Research output: Contribution to journalArticlepeer-review

12 Scopus citations

Abstract

Atomic force microscopy, Thioflavin T (ThT) fluorescence assay, circular dichroism spectroscopy, differential scanning calorimetry, and molecular modeling techniques have been employed to investigate the amyloid aggregation of insulin in the presence of non-ionic detergent, Triton X-100 (TX-100). In contrast to recently described inhibition of lysozyme amyloid formation by non-ionic detergents (Siposova, 2017), the amyloid aggregation of insulin in the presence of sub-micellar TX-100 concentration exhibits two dissimilar phases. The first, inhibition phase, is observed at the protein to detergent molar ratio of 1:0.1 to 1:1. During this phase, the insulin amyloid fibril formation is inhibited by TX-100 up to ∼60%. The second, “morphological” phase, is observed at increasing detergent concentration, corresponding to protein:detergent molar ratio of ∼1:1 - 1:10. Under these conditions a significant increase of the steady-state ThT fluorescence intensities and a dramatically changed morphology of the insulin fibrils were observed. Increasing of the detergent concentration above the CMC led to complete inhibition of amyloidogenesis. Analysis of the experimental and molecular modeling results suggests an existence of up to six TX-100 binding sites within dimer of insulin with different binding energy. The physiological relevance of the results is discussed.

Original languageEnglish (US)
Pages (from-to)709-718
Number of pages10
JournalColloids and Surfaces B: Biointerfaces
Volume173
DOIs
StatePublished - Jan 1 2019
Externally publishedYes

Keywords

  • Amyloid aggregation
  • Insulin
  • Morphology of fibrils
  • Triton X-100-insulin interaction

ASJC Scopus subject areas

  • Biotechnology
  • Surfaces and Interfaces
  • Physical and Theoretical Chemistry
  • Colloid and Surface Chemistry

Fingerprint

Dive into the research topics of 'Dual effect of non-ionic detergent Triton X-100 on insulin amyloid formation'. Together they form a unique fingerprint.

Cite this