Dual effect of non-ionic detergent Triton X-100 on insulin amyloid formation.
Colloids Surf B Biointerfaces
; 173: 709-718, 2019 Jan 01.
Article
en En
| MEDLINE
| ID: mdl-30384267
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 10.1 to 11. During this phase, the insulin amyloid fibril formation is inhibited by TX-100 up to â¼60%. The second, "morphological" phase, is observed at increasing detergent concentration, corresponding to proteindetergent molar ratio of â¼11 - 110. 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.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Octoxinol
/
Proteínas Amiloidogénicas
/
Agregado de Proteínas
/
Amiloide
/
Insulina
Límite:
Humans
Idioma:
En
Revista:
Colloids Surf B Biointerfaces
Asunto de la revista:
QUIMICA
Año:
2019
Tipo del documento:
Article