Protein folding aggregation prevention

Before protein molecules attain their native folded state they may expose hydrophobic patches to the solvent. Isolated purified proteins will aggregate during folding even at relatively low protein concentrations. Inside cells, where there are high concentrations of many different proteins, aggregation could therefore occur during the folding process. This is prevented by... 

FIGURE 4-30 Chaperones in protein folding. The cyclic pathway by which chaperones bind and release polypeptides is illustrated for the . coli chaperone proteins DnaK and DnaJ, homologs of the eukaryotic chaperones Hsp70 and Hsp40. The chaperones do not actively promote the folding of the substrate protein, but instead prevent aggregation of unfolded peptides. For a population of polypeptides, some... 

Some complex proteins fold only in the presence of other proteins called chaperones. Although the ways in which chaperones facilitate protein folding is still under investigation, it appears likely that they prevent the formation of aggregates that interfere with normal folding. 

Molecular chaperones, which bind and stabilize un folded or partly folded proteins, thereby preventing these proteins from aggregating and being degraded... 

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