CONFORMATIONAL BEHAVIOR OF TRIS-STABILIZED BOVINE SERUM ALBUMIN WHEN INTERACTING WITH CATIONIC SURFACTANT
Rubrics: 1. CHEMISTRY
Authors:
1.
Kazan National Research Technological University
2.
KNITU
Type:
Article
Pages:
from 11
to 17
Status:
Published
Received:
31.01.2026
Accepted:
31.01.2026
Published:
31.01.2026
Language:
Russian
Keywords:
PROTEIN-LIPID INTERACTIONS, BOVINE SERUM ALBUMIN, DODECYL TRIMETHYLAMMONIUM BROMIDE, TRIS-STABILIZED PROTEIN, CONFORMATION, X-POTENTIAL, TRYPTOPHAN HYDROPHOBIZATION
Abstract:
To establish the relationship between conformational behavior and intermolecular interactions in the lipid-protein system, changes in size, x-potential, and tryptophan fluorescence of bovine serum albumin (BSA) in the presence of the cationic surfactant dodecyl trimethylammonium bromide (DTAB) in Tris-buffered aqueous solutions (pH=7.3) were studied. At this pH value, Tris-buffered BSA exists as a globular macroanion with a x-potential of minus 4 mV and an average size of 11 nm. As DTA cations bind, BSA macroanions are neutralized and compacted. At a molar ratio of DTA:BSA=100, DTA-BSA associates reach an isoelectric state and exhibit a trimodal size distribution (7, 10, and 14 nm). When the CMC of surfactants in the DTAB micellar solution is exceeded (DTAB:BSA ratio = 1000), DTA-BSA associates become positively charged with a x-potential of plus 2.7 mV and exhibit a bimodal size distribution (10 and 20 nm). Conformational changes are accompanied by hydrophobization or dehydrophobization of the tryptophan environment in the BSA macromolecule volume.
To establish the relationship between conformational behavior and intermolecular interactions in the lipid-protein system, changes in size, x-potential, and tryptophan fluorescence of bovine serum albumin (BSA) in the presence of the cationic surfactant dodecyl trimethylammonium bromide (DTAB) in Tris-buffered aqueous solutions (pH=7.3) were studied. At this pH value, Tris-buffered BSA exists as a globular macroanion with a x-potential of minus 4 mV and an average size of 11 nm. As DTA cations bind, BSA macroanions are neutralized and compacted. At a molar ratio of DTA:BSA=100, DTA-BSA associates reach an isoelectric state and exhibit a trimodal size distribution (7, 10, and 14 nm). When the CMC of surfactants in the DTAB micellar solution is exceeded (DTAB:BSA ratio = 1000), DTA-BSA associates become positively charged with a x-potential of plus 2.7 mV and exhibit a bimodal size distribution (10 and 20 nm). Conformational changes are accompanied by hydrophobization or dehydrophobization of the tryptophan environment in the BSA macromolecule volume.
Keywords:
PROTEIN-LIPID INTERACTIONS, BOVINE SERUM ALBUMIN, DODECYL TRIMETHYLAMMONIUM BROMIDE, TRIS-STABILIZED PROTEIN, CONFORMATION, X-POTENTIAL, TRYPTOPHAN HYDROPHOBIZATION
PROTEIN-LIPID INTERACTIONS, BOVINE SERUM ALBUMIN, DODECYL TRIMETHYLAMMONIUM BROMIDE, TRIS-STABILIZED PROTEIN, CONFORMATION, X-POTENTIAL, TRYPTOPHAN HYDROPHOBIZATION
