A Glimpse into the Initial Microsecond of Biomolecular Condensation.

Area of Science:

• Biochemistry
• Molecular Biology
• Biophysics

Background:

• Biomolecular condensation is essential for cellular function.
• The initial stages of phase transition during condensation are not well understood.

Purpose of the Study:

• To investigate the molecular events and kinetics during the first microsecond of peptide condensation.
• To elucidate the role of different molecular forces in the early stages of biomolecular phase transitions.

Main Methods:

• Temperature jump infrared spectroscopy was employed to probe rapid structural changes.
• Molecular dynamics simulations provided high-resolution insights into the condensation process.

Main Results:

• Intrinsically disordered proteins undergo structural transitions and assembly on ultrafast timescales.
• Backbone hydrogen bonding, rather than hydrophobicity, was identified as the primary mediator for stabilizing local structures during initial condensation.
• Hydrogen bonds facilitate the formation of stable interaction interfaces, enabling preorganized conformations.

Conclusions:

• Hydrogen bonding plays a critical role in the ultrafast condensation of hydrophobic polypeptides.
• This mechanism allows disordered proteins to adopt specific conformations and influences assembly kinetics in cellular environments.