A guide to studying protein aggregation

Abstract

Disrupted protein folding or decreased protein stability can lead to the accumulation of (partially) un-or misfolded proteins, which ultimately cause the formation of protein aggregates. Much of the interest in protein aggregation is associated with its involvement in a wide range of human diseases and the challenges it poses for large-scale biopharmaceutical manufacturing and formulation of therapeutic proteins and peptides. On the other hand, protein aggregates can also be functional, as observed in nature, which triggered its use in the development of biomaterials or therapeutics as well as for the improvement of food characteristics. Thus, unmasking the various steps involved in protein aggregation is critical to obtain a better understanding of the underlying mechanism of amyloid formation. This knowledge will allow a more tailored development of diagnostic methods and treatments for amyloid-associated diseases, as well as applications in the fields of new (bio)materials, food technology and therapeutics. However, the complex and dynamic nature of the aggregation process makes the study of protein aggregation challenging. To provide guidance on how to analyze protein aggregation, in this review we summarize the most commonly investigated aspects of protein aggregation with some popular corresponding methods.

Inhibitory Effect of DMSO on Halohydrin Dehalogenase: Experimental and Computational Insights into the Influence of an Organic Co‐solvent on the Structural and Catalytic Properties of a Biocatalyst

“…Protein structural transformations of different extent may lead to changes in its size and shape, which can be identified using the dynamic light scattering (DLS) technique. The increase in size greater than the one found in the crystal structure of an enzyme is usually attributed to protein aggregation [53] . Thus, we chose DLS to evaluate the influence of DMSO concentration on the global structure of HheC.…”

“…After 120 h, there are no particles smaller than 40 nm left, and their size extends to 6 μm. When protein is exposed to a denaturing agent, the shift in its size to larger particles is commonly ascribed to random protein rearrangement into a looser structure and molecular aggregation [53] . Under harsh conditions, denaturation and protein unfolding may occur, followed by rapid and unspecific aggregation due to hydrophobic interactions among unfolded chains [55] .…”

“…The increase in size greater than the one found in the crystal structure of an enzyme is usually attributed to protein aggregation. [53] Thus, we chose DLS to evaluate the influence of DMSO concentration on the global structure of HheC. Number size distribution (NSD) and volume size distribution (VSD) were used to characterize the distribution of particles with a different hydrodynamic diameter (D h ).…”

“…denaturing agent, the shift in its size to larger particles is commonly ascribed to random protein rearrangement into a looser structure and molecular aggregation. [53] Under harsh conditions, denaturation and protein unfolding may occur, followed by rapid and unspecific aggregation due to hydrophobic interactions among unfolded chains. [55] This effect occurs faster at higher concentrations of OSs, especially hydrophilic ones.…”

A comparison of four technologies for detecting p53 aggregates in ovarian cancer

“…Moreover, mutated p53 is not the only tumor suppressor protein with enhanced aggregation tendency. In silico analyses demonstrated that protein aggregation is not a rare phenomenon, but far more common, and other tumor suppressor proteins, such as PTEN or Axin, have been identified to form amyloid-like structures ( 44 – 47 ). Our herein mentioned tools can be easily adapted to detect other types of amyloid-like proteins and help to evaluate their biological and clinical relevance in various cancer types.…”