Macromolecule-assisted de novo protein folding

Area of Science:

• Biochemistry
• Molecular Biology
• Cell Biology

Background:

• Newly synthesized polypeptides are intrinsically linked to macromolecules like ribosomes during protein synthesis and folding in vivo.
• The impact of these linkages on endogenous polypeptide aggregation has been overlooked, despite macromolecules' known solubilizing effects in protein technologies.
• Understanding these linkage effects is crucial for refining models of de novo protein folding.

Purpose of the Study:

• To investigate the role of macromolecule linkages in the aggregation of newly synthesized polypeptides.
• To explore how intrinsic macromolecule properties influence protein folding and prevent aggregation.
• To integrate the effects of macromolecule linkages into the mechanisms of de novo protein folding.

Main Methods:

• The study focuses on theoretical considerations and existing evidence regarding macromolecule-polypeptide interactions.
• Analysis of established principles of protein folding and molecular chaperone activity.
• Review of data on the impact of surface charges and excluded volume of macromolecules on protein stability.

Main Results:

• Macromolecule linkages, previously assumed to be neutral in aggregation, significantly impact polypeptide behavior.
• Intrinsic properties of macromolecules, such as surface charge and excluded volume, are key factors in preventing polypeptide aggregation.
• These macromolecules can act as "folding helpers," maintaining nascent chains in a folding-competent state.

Conclusions:

• Macromolecules linked to nascent polypeptides play a vital role in preventing aggregation during de novo protein folding.
• The stabilizing effects are attributed to macromolecule properties like surface charge and excluded volume, not just simple linkage.
• This linkage-based folding assistance offers new perspectives on intracellular protein folding mechanisms.