title: Investigating the effects of sodium dodecyl sulfate on the aggregative behavior of hen egg-white lysozyme at acidic pH.
abstract: The research presented here is aimed at examining the effects of sodium dodecyl sulfate on the aggregative behavior of hen egg-white lysozyme at pH 2.0. Through various spectroscopic techniques, dynamic light scattering, and electron microscopy, we first demonstrated that SDS exhibited a biphasic effect on lysozyme fibrillation. The presence of SDS at higher concentrations (e.g., 0.25, 5.00, or 20.00 mM SDS) was found to suppress fibril formation of lysozyme whereas fibrillogenic lysozyme-SDS ensemble containing beta-sheet-rich conformation was observed upon the addition of lower concentrations of SDS (e.g., 0.00, 0.06, or 0.1mM SDS). Next, our equilibrium urea-unfolding data revealed that lysozyme samples with higher SDS concentrations showed superior thermodynamic stabilities over the ones with no or lower levels of SDS. Finally, the correlation between SDS concentration and lysozyme aggregative/fibrillogenic propensity and the underlying interacting mechanism were further explored using surface tensiometry and isothermal titration calorimetry. We believe the outcome from this work may not only help decipher the molecular mechanism of amyloid fibrillation, but also shed light on a rational design of potential therapeutic strategies for amyloid pathology.
authors.affiliation: Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan.
authors.forename: Ying-Tz
authors.initials: YT
authors.lastname: Hung
authors.forename: Ming-Shen
authors.initials: MS
authors.lastname: Lin
authors.forename: Wen-Yih
authors.initials: WY
authors.lastname: Chen
authors.forename: Steven Sheng-Shih
authors.initials: SS
authors.lastname: Wang
mesh_terms: D000143:Acids / Q000737:chemistry / Q000494:pharmacology; D000818:Animals; D002151:Calorimetry; D002645:Chickens; D002942:Circular Dichroism; D004305:Dose-Response Relationship, Drug; D005260:Female; D006863:Hydrogen-Ion Concentration; D046529:Microscopy, Electron, Transmission; D009113:Muramidase / Q000737:chemistry* / Q000648:ultrastructure; D011487:Protein Conformation / Q000187:drug effects; D017510:Protein Folding; D055550:Protein Stability / Q000187:drug effects; D017433:Protein Structure, Secondary; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry* / Q000494:pharmacology; D013050:Spectrometry, Fluorescence; D013816:Thermodynamics; D014508:Urea / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000143:Acids; D012967:Sodium Dodecyl Sulfate; D014508:Urea; C421864:hen egg lysozyme; D009113:Muramidase