SDS can be utilized as an amyloid inducer: a case study on diverse proteins

Area of Science:

• Biochemistry
• Biophysics
• Structural Biology

Background:

• Sodium dodecyl sulfate (SDS) is an anionic surfactant with properties mimicking biological membranes.
• SDS is known to induce protein aggregation.
• Protein aggregation, particularly amyloid formation, is implicated in various diseases.

Purpose of the Study:

• To investigate the conditions under which SDS induces amyloid formation in diverse proteins.
• To elucidate the role of electrostatic interactions in SDS-induced protein aggregation.
• To identify potential strategies for preventing amyloid formation.

Main Methods:

• Circular dichroism spectroscopy
• Fluorescence spectroscopy
• Dye binding assay
• Electron microscopy
• Study of 25 diverse proteins

Main Results:

• SDS induced amyloid formation in all 25 proteins tested at a pH below two units of their isoelectric points (pI).
• No aggregation was observed at a pH above two units of pI.
• Electrostatic interactions were identified as the primary driver of SDS-induced amyloid formation.

Conclusions:

• Protein aggregation into amyloid structures can be induced by SDS under specific pH conditions.
• Electrostatic interactions are crucial for initiating amyloid formation.
• The findings may guide the development of therapeutic molecules to counteract amyloid formation.